Research On Mechanism Of Pressure Pulsations Of Piston Pump On Vibration Characteristics Of Hydraulic Excavator

With the development of hydraulic excavators towards safety and comfort,the related industries have higher and higher requirements on the dynamic performance of hydraulic excavators.As the power source and key component of hydraulic excavator hydraulic system,the piston pump will produce pressure pulsations when working.The pressure pulsation of the piston pump will not only lead to the violent vibration of all parts of hydraulic excavator,but also cause some unexplained abnormal vibration behavior of hydraulic excavator,affecting the safety and comfort of operators.The main reason is that the research on the influence mechanism of pressure pulsation of piston pump on vibration characteristics of hydraulic excavator is not enough.Therefore,studying the influence mechanism of piston pump pressure pulsation on the vibration characteristics of hydraulic excavator seems more significant to reduce the vibration of hydraulic excavator.The purpose of this paper is to investigate the influence mechanism of pressure pulsation of piston pump on the vibration characteristics of hydraulic excavator.The main contents include:The dynamic model of hydraulic excavator with piston pump is established.First,the mechanics model of piston pump subsystem is built,and then mechanical model of Engine-Piston Pump System is established considering the impact of the engine on the piston pump.Then,the mechanical model of hydraulic excavator including piston pump is built by considering the working principle and structural characteristics of hydraulic excavator.On this basis,the dynamic model of hydraulic excavator including engine,piston pump,rotary platform and cab is established,which lays a theoretical foundation for studying the vibration characteristics of hydraulic excavator.According to the complicated excitation characteristics of hydraulic excavator under different working conditions,this paper investigates three main excitation characteristics of hydraulic excavator,namely,piston pump pressure pulsation excitation characteristics,engine excitation characteristics and road excitation characteristics.The model diagram of the vibration transmission path is obtained by analyzing the vibration transmission path of hydraulic excavator under the action of the three main excitations,which provides a theoretical basis for further studying the influence mechanism of pressure pulsation of piston pump on the vibration characteristics of hydraulic excavator.Based on the dynamic model of hydraulic excavator,the vibration characteristics of hydraulic excavator are analyzed by a instance and the influence mechanism of pressure pulsation of piston pump on vibration characteristics of hydraulic excavator under complicated working conditions is investigated.The internal relationship between the vibration characteristics of hydraulic excavator and the pressure pulsation of piston pump under complicated working conditions is revealed and some beneficial conclusions are obtained.Finally,the theoretical analysis results are verified by field experiments.