Research On Reliability Of Railway Signal Relay Under Vibration

In recent years,China's rail transit industry has developed rapidly,and a better transportation environment has met people's travel and transportation needs.With the continuous increase of the operating speed of EMUs,higher requirements have been put forward on railway transportation safety and riding comfort,and the performance index requirements for railway electrical equipment have also increased.Reed-type railway signal relays are widely used in railway systems,so whether the contacts can be reliably contacted directly affects train safety and the normal operation of the railway system.On the one hand,the vibration problems of switching appliances,on the one hand,whether the contacts can be reliably contacted under external vibration or shock load;on the other hand,the contact bounce problem caused by contact closure also affects the electrical life and contact performance of the contact spring system.have a great impact.In this paper,the contact spring system of a certain type of railway signal relay is taken as the research object,and the combination of theoretical analysis and computer simulation is used to conduct in-depth research on the mechanical properties of the reed under vibration.Firstly,based on the nonlinearity of the contact between the dynamic and static contacts as the starting point,based on the bending vibration theory of the cantilever beam,a simulation model of the relay contact spring system was constructed based on the finite element calculation method,and a modal analysis was performed to obtain its natural frequency and formation;Using Newmark's implicit dynamic analysis algorithm,by applying a fixed frequency vibration excitation load to the base,the contact contact force,the maximum stress value of the reed and the displacement of the contact with time are obtained;based on the modal superposition method for the contact spring The system performs harmonic response analysis to obtain the contact force of the contact and its change in the frequency domain response;compares and analyzes the different vibration responses of the contact spring system in the finite and infinite positions,and explores the effect of the limit structure on the anti-vibration performance of the railway signal relay And the correctness of the simulation model was verified by shaking table vibration experiments.Secondly,by applying two kinds of shock pulse loads of half sine and positive and negative triangle waves,the contact force change curve of the contact under the impact state is obtained,and several factors affecting the impact resistance performance of the contact spring system are considered.The effects of different impact acceleration amplitudes,different pulse widths,gravity directions,and different prestressing forces on their impact resistance performance were obtained through comparative analysis.The relationship between the maximum reed stress value and the impact acceleration amplitude was obtained,and different impacts were explored.Response of dynamic change of contact force of contact spring system under pulse waveform.Finally,based on the rigid-flexible multi-body dynamics theory and ADAMS virtual prototype simulation technology,a dynamic characteristic simulation model of a rigid-flexible coupled spring system is constructed and simulated.The contact force variation curves under different parameters are obtained.Through comparative analysis,the key factors affecting the dynamic characteristics of the relay are summarized,and an effective method for suppressing the bounce of the contacts of the railway signal relay is proposed.The research results of this topic can provide reference significance for the design and development of railway signal relays,and can also provide new ideas for the simulation research of contact reliability of reed-type electrical switches.