Research On Gear Modification Of The Gearbox Of Concrete Transport Vehicle

In the field of engineering machine,wind power…etc. Gear transmission is developing toward the direction of low speed and heavy load,high speed and heavy load. this puts forward higher requirements in the aspect of high reliability,long life. the gear modification technology is an important means of developing the heavy load,long life and high reliability gear transmission. This thesis did some research on the gearbox for concrete transport vehicle, carried out the system deformation analysis for the gearbox at the rating load, analyses the transmission error of gear mesh and lead load distribution, and according to the principle of gear modification, proposed a kind of method for profile modification and lead modification, finally verified that the gear modification parameter was reasonable by the test. The major work is summarized as follows:(1) Introduced the theory of gear contact analysis, including the Hertz elastic contact theory and the loaded tooth contact analysis theory, and provided the theory foundation for gear contact analysis of gearbox.(2) Built up the analysis mode of gear transmission system by the MASTA and ANSYS software, and analyses the influence of different stiffness of carrier and housing on gear mesh misalignment .the result indicated the stiffness of carrier and housing has important impact on the magnitude and direction of gear mesh misalignment.(3) Introduced the principle of profile modification and the method of determining profile modification parameter. At the different amount of gear modification and load case, analyses the gear mesh transmission error, and determined the optimum parameters of profile modification. Contact analysis results showed that the profile modification can reduce the gear modification and improve the stability of gear transmission.(4) Introduced the principle of lead modification and the method of determining lead modification parameter. Conducted the system deformation analysis of gearbox, and obtained the deformation of gear shaft, provided the initial condition for determining the lead modification parameter. Compared to the tooth load distribution of different amount of lead modification, determined the optimum parameter of lead modification. Contact analysis results indicated that the lead modification can improve the tooth face load distribution and increase the gear contact and bending fatigue strength.(5) Described the loaded tooth surface fatigue test, and checked the tooth contact pattern after test. The results verified the parameter of gear modification was reasonable. Introduced the basic principles and test load, and compared the shear force of secondary sun gear which gained by calculating in software and which gained by experiment.