Research On The Design Of Marine Beveloid Gears And Characteristics Of Nonlinear Oscillations

Shipbuilding industry is developing more and more rapidly. For the propellercan get a better water entry angle, the driving device between main engine andpropeller must be compact, the installation location of marine diesel should be aslow as possible and the cabin altitude should be lowered to adapt the center ofgravity of hull and increase the stability of the hull. These requirements will lead tothe narrow space problem of marine gearbox. Beveloid gear pair, a new form of geartransmission, has a lot of outstanding advantages such as good stiffness, small toothclearance, high strength, high efficiency and excellent adaptability to adjust gearbacklash and so on.This thesis is based on the project “study on the gear systems with parametricexcitation by the homotopy analysis method” supported by Natural ScientificResearch Innovation Foundation in Harbin Institute of Technology (HIT. NSRIF.2011107), the project “study on the design of marine beveloid gear pair andnonlinear dynamics by the homotopy analysis method” supported by ShandongProvincial Natural Science Foundation (Approval No. ZR2012EEM018) and theproject “study on spatial noninvolute beveloid gear transmission and homotopyanalysis method with Parametric Excitation” supported by National Natural ScienceFoundation of China (Approval No.51275108). Some intetesting phenomena suchas tooth meshing, parameter design and nonlinear oscillation characteristics arepresented. Based on space meshing theory and differential geometry, the toothprofile equation and meshing equation of noninvolute beveloid gears are deduced.These analysis results can help to develop the foundation of the design andmanufacture of beveloid gear pair. Based on generating principles and the imaginaryrack, the geometrical parameter of gears and the location relationship of rack cuttersare calculated in detail. Dynamics differential equations are established based onhomotopy analysis method (HAM), and these nonlinear dynamics phenomena withdifferent parameters and loads, such as primary resonance, superharmonic resonanc-es and subharmonic resonance, are all analyzed. Furthermore, the influence of staticloads, dynamic loads and damping coefficients on frequency response curves are analyzed thoroughly. These analysis results have more and more guiding significancefor reducing the vibration and noise in beveloid gear systems and can provide thebasic theory principles for tooth modification.