Failure Mechanism Of Block Brake And Wear Analysis Of Brake Shoe

Elevator,as one of the main means of transportation in buildings,is a special equipment involving the safety of people’s lives.In recent years,accidents of casualties and property losses caused by the failure of elevator brake are common.As one of the indispensable parts of elevator,once the brake breaks down,it may cause serious casualties.This paper takes DZD1-653 elevator block brake as the research object,carries out the research on its failure mode and failure mechanism,studies the wear mechanism of brake shoe and carries out simulation analysis.The main research work of this paper is as follows:In the first chapter,the background and significance of this paper are elaborated,the basic requirements and classification of elevator brake,the working characteristics of brake and the status quo of fault diagnosis are introduced,the research status and existing problems of brake shoe wear are analyzed,and the work content of this paper is put forward.In the second chapter,the composition and working principle of the block brake are analyzed;through the analysis of its working characteristics,a mechanical model to characterize its working characteristics is established;the potential failure of the block brake is studied by using fault tree analysis method,and the main failure mode is insufficient braking moment;through the analysis of the failure mechanism of the main failure mode,the wear of the brake shoe is selected as the characterization block brake.Degradation parameters of brake performance.In the third chapter,the contact model between brake shoe and brake wheel based on Hertz theory and the wear model of brake shoe based on Archard model are established by studying the material characteristics and wear mechanism of brake shoe.The mathematical relationship between the wear depth of brake shoe and the number of braking times is obtained by numerical calculation,and the mathematical relationship between the brake moment and the number of braking times of block brake is also obtained.In the fourth chapter,ABAQUS is used to analyze the ideal wear,eccentric wear and asymmetric wear of the brake shoe under different wear conditions.The contact stress of the brake shoe varies with the number of braking times.The fifth chapter summarizes the research contents of the whole paper and looks forward to the next step.