Research On Balance Error Calculation And Selective Assembly Methods Of The Three-cylinder Engine Balance Shaft System

The balance error of the balance shaft system of the three-cylinder engine is the key index to evaluate its balance performance,and the assembly of the balancing shaft system directly affects the size of the balance error,which further affects the running stability,vibration and noise of the three-cylinder engine.Therefore,it is necessary to ensure the assembly quality of the balancing shaft system of the three-cylinder engine.The main research work of this paper is as follows:(1)For the research of three cylinder engine balance shaft system assembly error influence on balance weight space position,based on Jacobian-Torsor model theory,the derivation and establish three cylinder engine balance shaft system of balance weight Jacobian-Torsor assembly error model,analysis of the three cylinder engine assembly characteristics of balance shaft system,establish the cooperate torsor expression and characteristic of Jacobian matrix,based on the analysis to get balance weight of A,B three-dimensional expression of the space position deviation and the changes in the direction of the vector field.(2)Based on the space pose errors of the balance weight of A and B,the relationship between the pose changes of the balance weight and the balance errors of the balancing shaft system of the three-cylinder engine is analyzed,according to the causes of the error system balance,establish the balance error model of three-cylinder engine balance shaft system,by the extremum method and statistical method,the variation range and distribution of the balance error of the three-cylinder engine balance shaft system under the influence of assembly error are obtained.(3)In order to determine the key machining errors affecting the system balance errors of the three-cylinder engine balance shaft,orthogonal experimental analysis was designed for the system balance errors,and the significance of the influence of the machining errors of each part on the system balance errors was obtained through variance analysis.Based on the orthogonal experiment results,the machining errors affecting the system balance errors are divided into critical machining errors and noncritical machining errors,and the critical machining errors are set as the conditions for the matching of the three-cylinder engine balance shaft system.(4)Taking the parts corresponding to the key machining errors as the parts participating in the selection,combining with the assembly structure and product characteristics of the balance shaft system of the three-cylinder engine,the optimization selection model of balance errors aiming at balance errors,parts utilization rate and balance quality fluctuation was established.Ant colony algorithm was used to solve the selection model,and the results were compared with the results of random assembly scheme to verify the reliability of the optimization selection model of the balance error of the three-cylinder engine balance shaft system.This paper analyzes the balance error of the balance shaft system of the threecylinder engine from the assembly angle,analyzes the influence of machining error on the assembly error of the balance shaft system,derives the balance error model,and analyzes the key machining errors that affect the balance error,and selects the key machining errors.The balance error is optimized to provide a technical basis for the control and matching of the balance error,which is beneficial to improve the balance performance of the balance shaft system of the three-cylinder engine.