The Study Of Multistage Non-linear Dual Mass Flywheel Damper

With the rapid development of the automobile industry and the continuous improvement of people's standard of living, people need more high-level demands for the comfort, this trend make reducing vibration and noise become an increasingly striking problem. Vehicle powertrain, the main sources of vibration and noise, has received extensive attention.Torsional vibration damper is an indispensable vehicle powertrain device for controling the torsional vibration. The clutch driven plate type torsional vibration damper born in the 1930s are gradually withdraw from the stage of history because of its own structural limitations, and it does not have the development potential in torsional vibration and noise control of the transmission system. The dual mass flywheel type torsional vibration damper (DMF) is a breakthrough invention of the vehicle powertrain torsional vibration controling technology. DMF appears in the middle 1980's. It has many strongpoints, and is easy to be used; so many automobile factories begin to pay attention to it. The first DMF appeared in German and Japan, and after it got success, many other countries, such as France, America, England etc., all began to research and develop the DMF. In the early 1990's the technology and products matured, and not only diesel car which was the first kind vehicle using it, but also other vehicles, such as gas engine car, bus, middle and low end car etc., begin to use it. And now in Europe, it is widely used in some kinds of vehicles.After nearly 20 years' development, dual mass flywheel has tended to structure mature, stable performance, and is widely used in various types of vehicles in foreign countries. But in our country it is not universal, there is no factory that produce dual mass flywheel. Some companies, research agencies and institutions produced a number of samples for the study. These product mostly concentrated on a single-stage linear elastic characteristics, but single-stage double mass flywheel exist a defect, it could not satisfy the performance and vibration buffer performance requirements. Therefore it is necessary for us to study multistage non-linear elastic characteristics. In this paper, the mainly work include the following:1. Based on the structure of dual-mass flywheel arc spring, design an innovation damping spring. This novelty spring makes stiffness from the single-class to multistage. It can improve the car's ride and carrying capacity with the traffic and load changes.2. Based on the dual mass flywheel design and development projects, studied on multistage non-linear spring dual-mass flywheel, establish parameter selection principle and design process of multistage dual mass flywheel.3. Established a discrete model of a domestic car powertrain vehicle. Develope natural frequencies and mode shapes inherent in the calculation procedure using MATLAB, forecasting and evaluation of multistage nonlinear dual mass flywheel torsional vibration control of the traffic conditions in the transmission and idling conditions.4. Simulation the multistage dual mass flywheel damping properties using ADAMS, analysis the performance of main parameters. Finally optimize its parameters, gain the design parameters of the optimal value.In this paper, research the multistage non-linear characteristics flywheel, develope a set of practical design methods and process. It not only can be used as reference for the vehicle powertrain vibration study, but also play a guiding role in the dual mass flywheel match for vehicle powertrain. This key to China's auto parts self-development capacity, as well as domestic car NVH rise in the level of control, this project has an important significance and practical value. I believe this technology will soon become popular in the country, and China's vehicles will use this type dual mass flywheel.