Calculation Of Efficiency And Analysis Of Load Sharing Characteristics Of Encased Differential Planetary Train Considering Tooth Friction

The encased differential planetary gear train is widely used in various areas of large power transmission with the advantages of large transmission power,high transmission efficiency and so on.The power cycle will appear if the structure of the system is unreasonable,which will seriously reduce the efficiency of system.The load distribution is of great significance to improving the transmission quality and service life of the system.The power flow,transmission efficiency,dynamic load sharing characteristics and floating characteristics of the encased differential planetary gear train used in large-power ship were studied,respectively.The kinematics and dynamics of the system were simulated using the virtual prototype technology ADAMS.The transmission ratio of the encased differential planetary gear train was derived,the influence of power allocation coefficient on power flow were analyzed.The necessary conditions with no power cycle of the system was obtained.The influence of different input power,input speed,tooth width,helix angle,modulus,pressure angle,roughness,lubricating oil viscosity on the efficiency was analyzed using the friction coefficient model based on elastohydrodynamic lubrication theory.The selection principle of structure parameters and lube oil of the system were obtained.The bending-torsion-shaft coupling dynamics model considering tooth surface friction was established,differential equations of system were founded by the method of lumped mass,the displacement and dynamic meshing force of the system were obtained by ODE45.The load sharing coefficients of the encased stage and differential stage were obtained.The load sharing characteristics of the differential stage and encased stage in different input speeds and input power were analyzed.The floating characteristics of the system were obtained and analyzed.The three-dimensional model of the encased differential planetary gear train was set up by UG,and the virtual assembly technology of the planetary gear train was elaborated in detailed,a simulation model of virtual prototype was founded in ADAMS.The contact force calculation model and contact stiffness calculation method were expounded.The dynamic transmission ratio of the system was obtained compared with the theoretical calculated values.The transmission efficiency and load sharing characteristics of the system were simulated and compared with the theoretical calculation values.