Research On Method Of Adjustment-free Design For Balanced Force Electromagnetic Relay Based On Process Parameter Matching

There is a problem of the balance force electromagnetic relays that the inconsistent output characteristics of the same batch and between batches in the manufacture.It will cause the final outputs unqualified directly,and needs the manual debugging afterwards.Through the analysis of its assembly process,it shows that manual participation is one of the main factors leading to unqualified performance.The qualification rate of the relay in the final step of assembly is the key point of this paper,which includes the operate voltage,release voltage,contact gap and contact pressure.Aiming at the key point,the name of adjusting-free rate are proposed,and the related calculation method is proposed by combining virtual prototype theory and consistency design principle.First of all,the paper elaborate and analyze the related concepts of adjustmentfree rate mentioned.There is no relevant theory and research of adjustment-free rate at present,so the definition of adjustment-free rate is given here and pointed out that this paper focus on the adjustment-free rate of the final assembly process.After that,the reasons for the low adjustment-free rate in the current manufacture and assembly process of this product are analyzed,and the overall design process of the adjustment-free rate is proposed based on the theory of Ternary Design.At the same time,the paper research on the design method of adjustment-free rate,and put forward the idea of using the enumeration method and the distribution method for the calculation.The specific calculation procedures of the respective methods were introduced respectively,and the feasibility of the method was verified through the calculation of the output characteristics.Then the virtual prototype model of the balance force electromagnetic relay is established.Firstly,the paper analyze the magnetization and demagnetization process of the nonlinear permanent magnet(PM),which occurs when the relay is debuggedg,and the migration law of the operate point of the PM during the magnetization and demagnetization process is studied.Based on the Preisach theory,the model of the non-linear PM is established.This model is also used in the virtual prototype model of static characteristics,and is verified by measured data.Then a virtual prototype model of the dynamic characteristics was established based on ADAMS,and the accuracy of the model was verified by the measured reaction force curve.Then a model of multsoftware co-simulation was carried out to obtain the parameter which is changing over time.Based on he previous results obtained by the finite element model,a fast calculation model of operate voltage and release voltage is established.Firstly,analyze the whole process of this product,and build a tree diagram of the overall assembly for the subsequent analysis.Then analyze the key points in the entire process;get the key input of the operate voltage and release voltage based on the analysis of parameters of the key process.Next,using the Optimal Latin Hypercube Sampling method to sample the selected parameters.The sample of input and output characteristics are established by the finite element method,and the fast calculation model of the operate voltage and release voltage is built based on the Kriging method.After normalization,the accuracy of the surrogate model is further improved based on the correlation theory of variogram.Finally,based on the fast calculation model,the parameter design and tolerance design of the adjustment-free rate are carried out,and the optimal scheme that meets the requirements is obtained through the parameter design,and then use the thory of robust tolerance design to improve the anti-interference ability of this product.Cobining the analysis of the craft and the guarantee design of process capability,the paper proposed the optimization scheme of contact gap,and verifies the effectiveness of the plan through manufacture.