| The lockup cluch is installed between pump and turbine of hydrodynamic torque converter. When the working situation is in the set point, the pump and the turbine will be locked by the lockup clutch through the control system of regulation, then, the hydrodynamic transmission is transformed into rigid mechanical transmission, so the lockup clutch is the device that can improve the transmission efficiency of the hydrodynamic torque converter. In abroad, some in-depth research and analysis of the lockup cluch in hydrodynamic torque converter has been developed. Equipped with hydrodynamic torque converter and the lockup clutch, the performance of the running and manipulation and fuel economy of vehicles can be greatly improved, such as bus, car, camion, tank etc. The lockup clutch is also used widely in the field of automatic transmission of car. The earlest devices of hydrodynamic transmission in our country appeared in 1950's. Now the hydrodynamic transmission has been paid more attention than before in our country. Research on the lockup clutch in hydrodynamic torque converter has been developed by many automobile manufacturers and research institutes.Study on lockup clutch in D240 hydrodynamic torque converter is made in this paper on the basis of"The Research on performance of D240 Torque Converter"of Shanxi Aerospace power hi-tech Co.Ltd. Which includes modeling and simulation of the lockup process of the lockup clutch. Then, the heat stress and vibration generated from the friction between platen in the lockup process are analyzed. The main coverage of this paper are as follows:â‘ Some knowledge is introduced and analyzed in the paper, such as the structure and working principle of the lockup clutch in hydrodynamic torque converter, the selection method of the locking point in process of locking, the calculation of sliding friction work and sliding friction power, the oil-filled property, the control system in process of locking, the control method and the development of the control technology.â‘¡The dynamic model of the vehicle transmission system is established, some assumption about working situation of the lockup clutch in hydrodynamic torque converter are made to simplify the model. For example, some unessential factors are ignored.Mathematical model of the lockup clutch under working situation is established according to dynamics simplified model. And the simulation system is made by using MATLAB/Simulink.When the pilot oil pressure is at 0.6MPa, 0.8MPa, 1.0MPa, the process of locking, the change curves of sliding friction work and sliding friction power are simulated respectively. The results under different pilot oil pressures are analyzed comparatively. The result of simulation is proven to be accurated after comparison with the experiment.â‘¢Different friction materials are introduced, and the property are comparatively analyzed among copper-base friction plate, iron base friction plate and paper friction material. The surface groove of friction plate are comparatively analyzed. The heat conduction process of friction plate is analyzed according to the heat conduction property. Three dimensional model of platen and friction plate are set up by using ANSYS software, then the model are meshed in ANSYS software too. Taking sliding work generated from the locking process as heat source, the distribution of temperature and the heat stress are simulated. The results of temperature and heat stress distribution are achieved, and the distribution of temperature and the heat stress are comparatively analyzed.â‘£The reason of vibration generated from the locking process of platen and friction plate is analyzed.Some assumption about vibration situation are made to simplify the model. Some unessential factors are ignored. Mathematical model of the vibration process of platen and friction plate are established by using MATLAB/Simulink software. The property curves of the vibration process of platen and friction plate are achieved.The analysis conclusion presented in this paper has guidance meaning for fuel economy and ride of vehicle, in the mean time, they are also fairly valuable for the application of the lockup clutch in hydrodynamic torque converter.
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