Research On Key Oil Distribution Technology Of Multi-action Inner Curve Radial Plunger Hydraulic Motor

Hydrostatic transmission has incomparable advantages with other transmission forms,and is widely used in walking machinery,the iron and steel industry,and civil engineering industries.As one of the core components of hydrostatic transmission: a multi-action inner curve radial plunger hydraulic motor,has the advantages of ultra-low speed operation,good stability,large output torque,and small pulsation.However,the radial piston motor also has some problems,such as large pressure differences in high and low-pressure distribution basins,low volume efficiency caused by leakage easily,large pressure impact,and flow pulsation,which seriously affect and limit the working performance and life of the radial piston motor.The oil distribution characteristics are the main factors affecting the above problems.Therefore,it is very necessary to analyze the dynamic characteristics and flow field characteristics of the multi-action internal curve hydraulic motor in the oil distribution process,optimize the valve plate parameters,and design a reasonable valve plate.The main work is as follows:1)Analyze the force of roller components and simplify the mechanical model;the process of oil distribution is analyzed according to the force of roller assembly.Derive the size of the valve plate.A Stator guide rail is designed based on the cosine function.Complete part modeling based on Pro/E.2)Complete motor assembly and kinematics simulation based on Pro/E.Based on Adams,complete the motor dynamics model establishment.The dynamic characteristics such as displacement,velocity,and pressure of the roller in oil inlet and oil outlet stages,as well as the periodic fluctuation law of motor output torque vibration are analyzed.3)Based on polar coordinates and relative motion analysis,the compound motion of translation and rotation in fluid domain is decomposed.The transient flow characteristics of a complete cycle of high and low pressure oil distribution are analyzed by pretreatment that affects the transient convergence of the flow field.The evolution of the overall flow field,the pressure distribution of the valve plate,the velocity variation on the gap oil film,the pressure variation in the plunger cavity,and the flow variation at the inlet and outlet are analyzed and summarized.4)For the valve plate,the structure of diameter fine-tuning enlargement and different forms of damping groove are designed for unloading,and the transient simulation of motor fluid domain is done.The characteristics of the four flow fields in the process of oil distribution are compared and analyzed,such as the pressure variation in the plunger chamber,the oil film pressure field in the gap,the velocity field at the two equilibrium positions,and the flow variation at the inlet and outlet.The advantages and disadvantages of flow field characteristics of different unloading structures are summarized and the reasons are analyzed.The simulation results show that the U-shaped damping groove has the best effect on reducing motor flow pulsation.