Meshing And Mechanic Characteristics Of A New Cycloid Gear Drive

Compared with the involute gear drive,the cycloid gear drive has large contact ratio,small sliding rate and its uiniform distribution,and large speed ratio.These advantages make the cycloid gear drive more suitable for high and precision mechanical systems,such as aerospace,bionic robots and medical devices.Here,a new type of cycloid gear drive is studied.The drive consists of the traditional hypocycloid and the epicycloid repaired and spliced.For the new type cycloid gear drive,the analysis of the contact ratio,the meshing angle,the sliding rate and the contact stress are carried out.The-three dimensional modeling,motion simulation,finite element statics analysis and modal analysis of the drive are completed,and the experiment of the model machine is done.According to profile equation of the new cycloidal gear,the formula of contact ratio and meshing angle are derived.Changes of the contact ratio and mesh angle along with drive parameters are calculated by MATLAB software.The calculation formula of sliding rate is derived according to the meshing principle,and changes of the sliding rate along with drive parameters are compared with ones of the involute gear.The results show that the new cycloid gear has large contact ratio,small sliding rate and its uniform distribution.The calculation formulus of the curvature radius and contact stress are derived,and the influence of parameter variation on curvature radius and contact stress are analyzed.On this basis,the design of the two development interface is completed by using Visual Basic 6.0,and it is convenient to compare contact stress with the involute gear.The 3D modeling of the new cycloid gear drive system is done with Siemens NX10.0.The motion simulation is carried out to verify the correctness of the modeling and assembly.The static analysis and modal analysis of the drive mechanism are carried out by using ANSYS Workbench software.The equivalent stress nephogram and deformation diagram of the drive mechanism under the external static load are obtained.The natural frequency and modal shape diagram of the system are given,and the modal characteristics of different frequency segments are analyzed.The results show that the vibration of the drive is mainly the bending vibration of the outer gear and the output end cover.On the outer gear,the largest deformation occurs.The assembly and adjusting of the model machine are completed,and the drive efficiency experiment is carried out.The test system of hammer vibration is used to measure the natural frequency of the prototype.The results show that the measured frequency is near to calculated value which illustrate the calculated results in this paper.