| In view of the complex over-positioning structure of the RV reducer and the extremely high manufacturing and assembly accuracy requirements,the group has proposed a new type of Abnormal Cycloidal Gear(ACG)precision reducer based on the existing precision reducer research,and has studied its transmission principle,transmission mode and error sources,etc.The research shows that the The research shows that the gearbox has a large transmission ratio and a simple structure,However,more stringent requirements are put forward on the contact performance of gear tooth surface load distribution and meshing impact.In order to improve the contact condition of gear tooth surfaces,this paper takes ACG pair as the research object,focusing on the influence of tooth profile design,gear tooth error deformation on the modification parameters and modification methods.The main work of the paper is as follows.(1)Exploring the formation of the "cycloid-involute-cycloid" composite tooth profile of ACG,clarify the tooth shape parameters on the formation of ACG tooth profile law,starting from the design of the meshing line,derivation of ACG gear tooth profile equation and its conjugate tooth profile equation,establish the mathematical model of internal meshing ACG vice,research different contact position conditions The mathematical model of the internal meshing cycloidal gear pair is established to study the change of meshing performance under different contact position conditions,and to obtain the influence of tooth design parameters on transmission characteristics such as sliding rate,overlap and curvature.(2)Establish mathematical models of ACG with manufacturing and installation errors,and obtain the bending deformation,shear deformation,additional deformation and contact deformation of the gear teeth along the tooth profile under specific operating conditions in combination with the Weber energy method,so as to obtain the maximum profile modification amount of the gear teeth and determine the functional relationship between the modification parameters for the purpose of profile modification of the gear teeth.(3)According to the relationship between gear transmission load and gear tooth deformation,establish a mathematical model of the reshaped gear under the coupling of multiple parameters taking into account the error and deformation,study the influence of parallelism error on the size of tooth deformation and skewness,so as to obtain the size of the maximum tooth profile,and obtain the interrelationship between tooth profile,profile length and profile curve,in order to achieve the purpose of gear tooth profile reshaping.The interaction of tooth profile and tooth profile elastic deformation on the amount of tooth profile modification of cycloidal external gears is investigated by considering the profile modification and tooth direction modification of gear teeth.Using the cycloidal gear profile model and 3D modelling software,a 3D model of the modified cycloidal gear is constructed.(4)The finite element simulation models of the ACG before and after reshaping are established respectively,and the dynamic contact forms,contact stresses,stress of concentration areas and tooth top impact conditions of the ACG before and after reshaping are compared and analysed under different mounting errors to predict the effectiveness and feasibility of the gear reshaping solution.The study shows that the reshaped ACG reduces the contact stress on the top of the teeth and improves the meshing conditions,i.e.the contact area changes from a band before reshaping to an elliptical shape after reshaping,which is more conducive to the precision transmission of the gear. |
PDF Full Text Request