Analysis Of Positive Pressure Of Disc Brake For Mine Hoist And Its Detection Method

The hoist is a key equipment in coal mine production,the good operation of the hoist is of great significance in ensuring the production safety,efficiency and reliability of the coal mine production process.In the braking process of the hoist,if the braking force of disc brake is not enough,the braking torque will be less than 3 times of the maximum static moment,which will cause serious accidents.Once the accident occur,it will bring incalculable economic loss,even cause personnel casualties,which seriously impact the miners' families and even the country and society,the consequences could be disastrous.Constant deceleration braking of mine hoist is the best way to deal with emergency safety accidents in the braking process,and brake positive pressure is one of the key factors of deceleration.So it is necessary to analyze the braking positive force of the disc brake and research its detection method under the condition of constant deceleration.In this paper,based on the modeling method of multi-body system rigid-flexible coupling dynamics,the modeling theory of disc brakes containing rigid body and flexible body is studied and simulated by ANSYS software.The specific research work and achievements of this paper are as follows:Firstly,the purpose and significance of the dynamic characteristics of disc brakes are introduced.The composition,working principle and development of disc brakes and the research status of disc brakes at home and abroad are introduced emphatically.The main research contents of this paper are put forward.Secondly,the theoretical basis of the rigid-flexible coupling system is analyzed,and the contents of modal synthesis method,flexible body stress solving method and finite element method of section stress are introduced.The ANSYS Workbench software platform is briefly introduced,and the the software platform for numerical simulation analysis process is clearly illustrated by chart.Thirdly,according to the working principle of hoist constant speed braking hydraulic system,simulation of constant speed braking hydraulic system with all digital PID control was carried out in SimulationX software.The simulation results show that the change of the deceleration during the constant braking process is closely related to the positive pressure of the brake,and the change of the oil pressure in the actual working condition is obtained,which lay the foundation for analyzing the distribution of the positive pressure during constant braking.Fourthly,according to the actual structure design of the disc brake,UG software was used to build the 3D model of the disc brake.After the model was simplified,the finite element was introduced in software ANSYS,then the transient dynamic simulation analysis was carried out.Dynamic stress distribution cloud diagram and stress curve of flexible components in brakes were obtained.Finally,the force of each flexible part is analyzed and compared,then the components that can express the positive pressure were determined,which provide the foundation for the design of the subsequent positive pressure detection method.Fifthly,a method of real-time detection of positive pressure of disc brakes was designed based on the results obtained by simulation analysis of rigid-flexible coupling transient dynamics.The problems during the design of the strain sensor are described.The location and orientation of the strain gauges were determined by the finite element analysis.The corresponding bridge connection method was designed.Finally,the advantages of the method are described.Finally,the main research work and achievements of this paper are summarized,and the next work is forecasted.