Structure Optimization And Characteristics Of Flow Distribution Transition Zone Of Three-flow Axial Piston Pump

Compared with the valve control system,the pump control system has the characteristics of high energy efficiency,compact system,small throttling loss,low cost,green environmental protection,etc.Therefore,it is widely used in hydraulic systems.Although the development of pump control technology is relatively mature,for closed pump-controlled asymmetric cylinders,existing solutions need to add auxiliary pumps or valves to solve the problem of asymmetric flow.These methods will increase the complexity of the system,causing problems of low efficiency and high cost.In order to solve this problem,some scholars have proposed an axial piston pump with three flow distribution windows.It can be used in directly closed pump-controlled asymmetric cylinders.By adjusting the ratio of the distribution window area to achieve flow matching,good dynamic and static characteristics are obtained,which is conducive to promoting the development of pump control technology.But in the process of its operation,the flow pulsation and pressure shock generated in the non-dead-point transition area of the valve disc are relatively large,which is not conducive to its wide application in actual production and life.In order to solve this problem,this subject will optimize the structure of the flow transition zone of the axial piston pump with three flow distribution windows and propose a new flow distribution window structure.In this paper,based on the research of the axial piston pump fluid noise optimization,this paper analyzes the flow distribution mechanism of the axial piston pump with three flow distribution windows.Based on the mathematical model analysis,the pump simulation model was built with the help of Amesim.By studying the flow and pressure characteristics of the pump,a new distribution structure is proposed and its specific parameters are optimized.The specific research contents of this article are as follows:The first chapter introduces the background,significance and main content of this research.The development history of axial piston pump and closed pump control technology is summarized.Summarized the method of axial plunger pump to reduce flow pressure pulsation and noise.The second chapter analyzes the distribution principle and movement law of the axial piston pump with three distribution windows.By establishing a mathematical model of plunger motion,a mathematical model of the distribution area,and a mathematical model of leakage,a pump simulation model is built.The structure of the damping hole,triangular groove and U-shaped groove is calculated and analyzed specifically.The third chapter explains the cause of noise in the non-dead-point transition area through simulation analysis,proposes a new flow distribution scheme and analyzes its principle.And through the simulation comparison verification,the specific parameters are obtained.The fourth chapter studies the structural characteristics of damping hole-triangle groove and U-triangle groove by comparison,and analyzes the effects of different damping groove structure and parameters on the flow and pressure characteristics of the three-port axial piston pump.The results of the study show that the new distribution structure is a way of opening damping oil holes a and b in the upper dead point transition area and non-dead point transition area of the valve plate and adopting the oil channel L connection.This method can effectively reduce the flow pressure overshoot of the plunger cavity and the oil discharge port.When the positions of the oil holes a and b are set at about 8 °and 88 °,and the radius is about 0.65 mm,the flow pressure pulsation characteristics are good,and the flow pulsation rate is reduced to 10.25%.At the same time,the high-pressure oil in the non-dead point transition area is introduced into the plunger cavity in the upper dead point transition area,which can effectively play the role of preload in the upper dead point area.This method not only reduces the leakage of the pump,improves the overall efficiency of the pump,but also reduces noise,achieving the purpose of energy saving and environmental protection.At the same time,the influence of the triangular groove,U-shaped groove,damping hole-triangular groove and U-triangular groove structure on the pressure and flow characteristics of the pump is analyzed,and the comparative analysis is carried out through the simulation model.The simulation results show that the characteristics of the triangular groove and the u-groove can be obtained,and when the u-triangular groove structure is selected,the advantages of both can be combined to effectively reduce the flow impact and reduce the flow pulsation rate to 8.04%,so as to obtain better pump flow characteristics.