| The hydraulic vibrator is a mechanical device which converts hydraulic energy into periodic vibration of workpiece.It can be used in a variety of fields.Hydraulic vibrators currently have some problems such as high cost,complex structure,and low vibration frequency.According to the existing problems,this paper designs a rotary valve type variable frequency hydraulic vibrator,which uses the rotary valve to realize the flow distribution,avoiding the complicated structure and high price.At the same time,the vibration frequency is adjusted by the rotation speed of the rotary valve to achieve frequency conversion,and the problem of low vibration frequency is also solved.Firstly,according to the existing vibrator form,the overall design scheme of the vibrator system is determined,and the structure and working principle of the system are explained.According to the actual situation,the structural design of the key components of the system,such as the rotary valve and the vibrating cylinder,to determine its key parametersThe mathematical model and simulation model of the vibrator system are established.The influence of the design parameters on the working characteristics of the vibrator is studied by using the simulation software to analyze the vibrator system.According to the simulation,when the external load connected to the system is in the form of damping,its system characteristic is better than that of the load with elastic form.When the external load form connected to the system contains damping and elasticity,The vibration characteristics of the system are relatively poor;The vibration frequency of the system is mainly realized by the change of the rotating speed of the rotary valve.The output characteristics of the system will be affected by the change of main pump displacement.When studying the influence of the pipeline on the system,,the liquid sensation has a greater influence on the vibration characteristics,and when selecting a pipeline,try to select short tubes with high stiffness.Establishing the runner model of the rotary valve and simulation analysis of rotary valve,and studying the flow field characteristics of different turbulence models,inlet pressure,inlet shape and different opening conditions of the rotary valve.Through the simulation analysis of the flow field characteristics in the rotary valve,The standard k-? model has a small number of iteration steps and is relatively accurate;When the inlet pressure increases,the eddy current phenomenon at the oil outlet gradually increases;The change of the shape of the oil inlet will change the area of the connection between the oil inlet and the rotary oil groove,andincreasing the area,the impact of the fluid on the connection between the rotary valve and the inlet will be slightly reduced,but the impact on the rotary valve notch will increase;When the inlet is connected with the oil sink,the opening is better when the opening is fully opened than when the opening is smaller.Through modal analysis of the key components of the vibrator,it is possible to determine the resonant frequency of key components and whether the vibrator will be damaged when vibrating.The simulation results show that the vibration frequency of the vibrator designed in this paper will not produce resonance.The above research results are of great significance to the design theory and vibration characteristics of the rotary valve hydraulic variable frequency vibrator,and provide a certain theoretical basis for the optimal design of the hydraulic vibrator.There are 65 pictures,4 tables and 69 references in this article. |
