The Research Of Vibration And Fuzzy Reliability Design For Swing Movable Teeth Transmission

With the development of industrial technology, the vibration of machine products has come to be concerned day by day. Well dynamic characteristic has become one of the important struggling goals in product development and design. Analyzing dynamic characteristic of machine products as well as replacing traditional static design with advanced dynamic design so as to meet the needs of static and dynamic characteristic, low vibration and low noise of machine products is becoming a sure tendency in machine products designing methods.With a very vast application vista in industry, swing movable teeth transmission, which is used to transmit rotary motion and power between two shafts with same axis, is a new type of small teeth difference planetary gear drive. The design methods, such as the theory of mechanism dynamic design, the finite element method and the theory of fuzzy reliability etc, are introduced to study the vibration and structural parameters optimization design of the swing movable teeth drive system. The dissertation includes the following six aspects: a), the torsional vibration dynamic model of swing movable teeth transmission system; b). the torsional and flexural vibrations dynamic analyzing model of swing movable teeth drive; c). finite element analysis of vibration modes of swing movable teethtransmission reducer box; d). fuzzy reliability design for the driving shaft vibration of swing movable teeth reducer; e). the effects of structural parameters' change on engaging stiffness of swing movable teeth drive; f). the optimization design of fuzzy reliability of swing movable teeth drive.In accordance with dynamic characteristics of swing movable teeth drive, the torsional vibration dynamic model of swing movable teeth drive is developed and the vibration equation of the vibration system is established for the first time. The response of the vibration system is solved.The torsional and flexural vibrations of swing movable teeth transmission system is analyzed and the elasticity of driving shaft, the elasticity of output shaft bearings and the elasticity of movable teeth are taken into consideration. The dynamic analyzing model of swing movable teeth transmission system is established. The natural frequencies of the vibration system are obtained by using the iterative perturbation method.With the help of the software AutoCAD 2000 and the finite element analyzing software-"ZiRui" CAE, the solid model of swing movable teeth transmission reducer box is created and the finite element analyzing dynamic model of swing movable teeth transmission reducer box is established. And the modes of the vibration system are analyzed.By using the method of transfer matrix, the dynamic model of the driving shaft vibration of swing movable teeth reducer is built. The calculation formula for natural frequencies of the flexural vibration of the driving shaft is derived. The theory of fuzzy reliability design is applied to study the anti-vibration design of the driving shaft of swing movable teeth reducer. The randomness of working frequency and the fuzziness of the critical speed bonder are discussed. The corresponding formulae of calculating the fuzzy reliability are presented.By changing the structural parameters of swing movable teeth drive, and by using the finite element software system to make large quantities of numerical calculation, the different curves of meshing stiffness of swing movable teeth drive are obtained. The change laws of meshing stiffness of swing movable teeth driveare studied, and the effects of structural parameters' change on meshing stiffness of swing movable teeth drive are discussed.The theory of fuzzy reliability design is applied to the optimization design of movable teeth drive. The method of the fuzzy reliability optimization design of swing movable teeth drive is proposed. The mathematical model of two-objective fuzzy reliability optimization design for swing movable teeth drive is put forward. A numerical example is given.