Research On Alternating Loading Technology Of Linear Oscillation Motor And Its Application

In the prior art,materials,components or devices in many fields need to be tested for stability before actual use to determine the reliability of the quality.The commonly used test equipment is a fatigue testing machine.The fatigue testing machine is a testing device for measuring metal or mechanical properties of components at room temperature and is widely used in many fields.At present,there are mainly widely used fatigue testing machines of electro-hydraulic servo type and electromagnetic resonance type.The electro-hydraulic servo tester has a large output force value and a large displacement stroke.However,the utilization rate of energy is low,less than10%.The electromagnetic resonance type tester can realize fatigue test,and high utilization of energy,but its displacement stroke is short,it is easy to be restricted by use,and the force value waveform is not good.In view of the problems arising from these two problems,this paper proposes a feasible idea of using a linear oscillating motor as a vibration exciter in a high frequency testing machine.The linear oscillation motor has the advantages of wide frequency range,good force value waveform,large displacement stroke and good controllability.This paper takes linear oscillation motor and frequency testing machine as the research object.The main research work is as follows:(1)The linear oscillation motor is used as the vibration exciter of the resonant fatigue tester.The working principle of linear oscillating motor is expounded.According to the characteristics of linear oscillating motor,its dynamic equation,electromagnetic model,equivalent circuit model and mechanical model are established,and relevant theoretical analysis is carried out.(2)According to the working principle of the fatigue testing machine,it isequivalent to the three-degree-of-freedom vibration system,and then the dynamic model is established.The force analysis is carried out to calculate the theoretical magnification of the main vibration system under resonance.(3)Using the finite element analysis software,the modal analysis and harmonic response analysis of the three-dimensional structure,analysis of the quality of the vibration weight,the diameter of the test piece,the mass of the mover component,the material of the mover component,the mass of the upper beam,The placement position of the vibration exciter and the stiffness of the sensor affect the natural frequency of the test piece loading system,and an effective method for improving the natural frequency of the vibration mode required by the loading system is obtained.The harmonic response analysis of the improved natural frequency structure is carried out,and the magnification at the test piece after the introduction of the damping coefficient is obtained.(4)The bow spring is selected as the elastic element,and the material is selected and applied to the static school core under the application of the ultimate force value.(5)Design the control circuit of the linear oscillating motor studied,and study the relationship between voltage frequency,voltage magnitude and the amplitude of the mover and the amplitude of the output force,and verify that the linear oscillating motor can be used as the vibration exciter of the test machine according to the test data.feasibility.