Research And Application Of Linear Motor Technology In Dynamic And Static Universal Testing Machine

Mechanical parts are the indispensable parts of machinery and machines.The production of every mechanical part needs to go through the process of material selection,design,analysis,and manufacturing.Each part has a service time and life under specific conditions.When designing,it needs to meet its specific requirements according to the actual working conditions.Some parts that have been subjected to alternating loads for a long time need to undergo a fatigue test to verify whether their life meets the design requirements,so as to ensure that the overall equipment will not be affected by the parts.In order to ensure the reliability of the parts,it is necessary to use the dynamic and static universal testing machine for fatigue test at this time.Universal testing machines are divided into static and dynamic.Static universal testing machines can only achieve static loading,such as static linear loading;dynamic universal testing machines must implement functions such as sinusoidal loading or random wave loading on the basis of static loading functions.The dynamic universal testing machine can simulate more working conditions than the static universal testing machine.This article studies a dynamic and static universal testing machine that can be both dynamic and static loading.Traditional universal testing machines are roughly divided into two types,one is electromagnetic,and the other is electro-hydraulic.In the fatigue test,fatigue vibration of 10 million times or more is defined as the fatigue failure will never occur.Therefore,for some tests,up to 10 million tests are required.At this time,the test time is included in the test.In cost.Effectively shorten the experiment time and greatly reduce the cost of the experiment.In the fatigue test,the biggest influence factor for time is the frequency of the dynamic and static universal testing machine.The high-frequency dynamic and static universal testing machine can effectively shorten the experiment time and reduce the cost of the experiment.The traditional electromagnetic type has high frequency characteristics,while the electro-hydraulic servo type does not have high frequency characteristics.Another indicator to measure the testing machine is the force value.The traditional electro-hydraulic fatigue testing machine has the characteristic of outputting a large force value,while the electromagnetic type uses the principle of electromagnetic resonance,which has a large output force and is not suitable for small force values.Aiming at the problem of electromagnetic testing machine with high frequency but unable to output small force value,and the problem of electro-hydraulic testing machine with large output force value but low frequency,this paper proposes the subject of studying the dynamic and static universal testing machine with linear motor as the actuator.Utilizing the linear motor’s fast response,100%transmission efficiency,large force value,precise control,and high frequency,using the linear motor as an actuator can give full play to the advantages of the linear motor and achieve a large output force range.Force to several thousand force;to achieve a wide frequency range,from below 1Hz to above 300 Hz.In addition,a resonance function is added to the motor to amplify the output force value,and the effect of amplifying the static maximum force value of3 k N to the dynamic 30 k N,which has the function of obtaining a larger output force with the same power.This article describes in detail the structural design principles of the key components of the fatigue testing machine.Through the comparison of the first and second generation structures,and the previous tests,the rationality of the second generation structure function is verified,and the shortcomings of the first generation structure will not appear;it will also be used for individual structures.The processing methods and material selection of complex parts will be explained;solutions will also be provided for some areas where gaps are guaranteed and difficult to assemble.After the structural design is completed,the stress conditions of key components are simulated,and finite element analysis is performed on the components,so that each key component meets the requirements in terms of force.In the control of the whole machine,use PID theory combined with the servo controller to draw the circuit principle diagram of the whole machine,and build the control system according to the drawn circuit principle diagram,and the selection of various components and the description of PID control theory.In the end,this article discusses the shortcomings of the whole machine and puts forward a prospect,and clarifies the direction of future improvement of the machine.