Study On The Characteristics Of Oil Film Between Slipper And Swashplate In Axial Piston Pump Considering Overturning

There are three key friction pairs in the axial piston pump:(1)Piston and cylinder;(2)Slipper and swashplate;(3)Cylinder Block and Valve Plate.Slipper and swashplate is mainly composed of slipper,swashplate,returning plate and other components.The lubricating between slipper and the swashplate is important factor for restricting the volumetric efficiency,mechanical efficiency,temperature rise,reliability and working life of the pump.Through the analysis of the cause of the failure of the pump,it is found that the wear problem of the slipper and the swashplate,that is the lubrication failure problem is one of the main factors causing the failure of the pump.This paper mainly studies the influence of lubrication performance between slipper and swashplate in the axial piston pump.The research focuses on the oil film characteristics under the overturning state of the slipper from the theoretical and experimental.By studying the effect of spindle rotation speed,working pressure on oil film thickness,leakage and friction,to guide the structural optimization design of slipper and swashplate.Mainly from the theoretical and experimental analysis of the lubrication performance of the slipper and swashplate,the theoretical: model the dynamic characteristics of the oil film in the overturning state of the slipper and swashplate;the experimental: design of the slipper test rig to verify the theoretical model of the slipper and swashplate.main content::(1)The working principle of the axial piston pump,the lubrication characteristics of the slipper and swashplate are introduced,the movement and force of slipper and swashplate of the axial piston pump are analyzed.The pressure field of the overturned slipper was modeled by the finite volume method.(2)The simulation research was carried out based on MATLAB.The influence of the spindle speed,working pressure and oil guiding hole structure parameters on the pressure of the slipper fluid pocket was analyzed.The pressure field and thickness field of the wedge oil film are solved numerically with the slipper fluid pocket pressure as the boundary condition.(3)The oil film characteristic test rig for slipper and swashplate of high-speed heavy-duty axial piston pump was designed and built,under different working conditions.the oil film thickness,leakage and friction of the slipper and swashplate was measured.The results show that:(1)Under the action of centrifugal torque and friction torque,the slipper will overturning effect and form a wedge-shaped oil film when it rotates,so the oil film characteristics of the slipper and swashplate cannot be analyzed according to the static pressure support,and the influence of various forces should be comprehensively considered.(2)In the oil discharge area,the positive pressing force of the slipper is large,and the pressure generated by the oil film and the anti-overturning moment are large,the thickness of the oil film and the angle of the overturning are small;the positive pressure of the sliding shoe in the oil suction area is positively pressed.,the force and the anti-overturning moment are large,so the thickness and of the oil film and the angle of anti-overturning are large.(3)It has been verified by experiments that when the spindle speed increase,the thickness of the slipper oil film will increase,but the inclination angle of the shoe will increase,which will easily cause friction and wear of the slipper.