| The basic components of a power reflux hydraulic transmission system include a hydraulic torque converter,a planetary gear transmission,and a constant-speed ratio gear transmission.The reverse placement of the torque converter in the return path has substantially reduced the power loss,and changes the transmission ratio of the entire system through continuous torque control of the torque converter and speed ratio conversion of the multi-speed transmission.Compared to traditional AT and other types of hydraulic transmission systems,the power reflux hydraulic transmission system not only retains the characteristics of the ground torque increasing torque and flexible connection that the torque converter itself has,but also has higher efficiency and speed ratio change.A wider range,more shock absorption buffer effect.Therefore,the back-flow hydraulic transmission system can make the vehicle get better power and economy.The specific research content of this paper is as follows:①The structural composition,external characteristics of the torque converter and the original characteristics of a dual-lead hydraulic torque converter used in this paper are introduced.A detailed description of the basic characteristics and evaluation indicators of the torque converter is given.A split-type transmission system obtained through a different connection scheme of a planetary gear train and a hydraulic torque converter is introduced,and the twelve types of external split forward transmissions with better performance and greater application value are used for hydraulic mechanical change.The structure of the torque converter is introduced.It lays the foundation for comparison with the static performance of the reflux torque converter.②Through the introduction of the structure of the power reflux hydraulic transmission system,and according to the parameters of the transmission hydraulic torque converter,its basic characteristics and evaluation indicators are derived.Determine the determinants of its basic parameters.The four types of external shunt transmission systems with comparatively good performance and application value were compared with those of the power reflux hydraulic transmission system for static characteristics comparison.The analysis summarizes the advantages and disadvantages of the return/split hydraulic drive system and the prototype hydraulic torque converter.By adjusting the parameters of the components of the power reflux hydraulic transmission system,a more excellent drive system is designed.③Since the resonance area of a six-cylinder diesel engine is between 40 and 150 Hz during operation,the resonating point of the reversible hydraulic transmission system should avoid its resonance region.Therefore,the dynamic model of the power reflux hydraulic transmission system is established,and the amplitude-frequency characteristic curves under different speed ratios are obtained.The effects of the stiffness and damping of the coupling on the amplitude-frequency characteristics of the power reflux hydraulic transmission system were studied.Simulation results show that by changing the stiffness and damping of the coupling,the resonance point of the power reflux hydraulic transmission system can be moved out of the resonance region of the engine.④Aiming at the complicated and varied working conditions of engineering vehicles,the test vehicle and the operating conditions of the simulated roadheader are designed.The simulation results show that the test vehicle adopting the power reflux hydraulic transmission system has its driving motor speed when it encounters abrupt load.Torque fluctuations are smaller than mechanical transmissions.Therefore,the power reflux hydraulic transmission system has the effect of protecting the power source and the transmission system. |
PDF Full Text Request