Contact Analysis Of Gear Driving With Meshed Medium Belt

The gear driving is a kind of solid contact transmission, relies on its teeth whichhave strict and certain geometric surface and are made of solid materials with a certaindegree of mechanical strength to transmit force and motion. Gear driving with meshedmedium belt is a new kind of gear driving，of which distinguished feature is a flexibleflat ring belt is placed on one gear of the traditional gear pair，the flexible belt isembedded between two meshing tooth surface by the teeth of gear pair naturally andorderly in the process of gear driving to become a meshed medium of a pair of metalgear teeth. The two metal tooth faces of this kind gear driving do not contact directlydue to the medium belt, so contact of gear pair turns to contact of “highmodulus(gear)-low modulus(medium belt)”.With contact pair type changing, the toothface of gear pair is not easy to damage,vibration and noise is decreased, gear toothmanufacturing accuracy is also decreased, so the manufacture costs will be greatlyreduced.How is its contact property, frictional behavior of metal and non-metalfriction pair and temperature rise situation of gear tooth and belt comparing withtraditional ordinary involute gear?All are the research core in this paper.1.The simplified contact model of gear driving with meshed medium belt ispreliminary established based on Merritt theory, which establishes foundation for itsfriction and lubrication mechanism study and corresponding mathematical-mechanicalmodel establishing. Contact stress of simplified model is calculated and analyzed byclassical contact mechanics method and elementary method, which providestheoretical bases for contact strength calculation.2.The friction and wear mechanism of metal and non-metal frictional pair isinvestigated and the failure forms of the medium belt is analyzed on the basis of itsstress analyzing.3.Based on ANSYS Workbench numerical analysis program, contact finite element model of gear with meshed medium belt is carried out for the first time andthe Von-Mises stress contour plot of gear tooth, the contact stress contour plot togetherwith the deformation of belt is got. Its max contact stress is compared with the sameparameter traditional involute gear on the same working condition. The result showsthat contact stress of gear with meshed medium belt is reduced, which is consistentwith theoretical prediction.4.Analysis on the effect of medium belt with different parameter property to thetransmission performance of gear with meshed medium belt is made by using the finiteelement method, and the results shows that the elastic modulus,thickness of belt andfriction coefficient between belt and gear tooth surface all affect the carrying capacityof gear pair.Contact stress changes greatly with the elastic modulus of mediumbelt.The carrying capacity of gear pair is not linearly related to the variation parameterof medium belt, contact strength,bending strength,stability of gear driving are allneeded to be consider and optimal design is needed to choose the best performancemedium belt.5.A3-D FE numerical simulation for gear with meshed medium belt is made anda steady-state temperature field distribution is got. The comparing analysis is carriedout between ordinary involute gear and the gear with meshed medium belt in the samegear parameters and running condition and the result shows that belt has smallinfluence on temperature field distribution of gear， but can decrease the maxsteady-state temperature. The medium belt has great temperature rise on the highrotation speed working condition as well, rotation speed of driving gear, friction factor,convection heat transfer coefficient and environmental al temperature parameters allhave influence on temperature rise. So, the gear driving with meshed medium belt isrecommended to be used on middle or low running speed working condition in orderto decrease the temperature rise of belt and make use of its advantage in great degree.