Research On The Monitoring System Of Mine Hoist

The mine hoist is one of the important mining equipments, it take the responsibility to contact the ground and the bottom of the mine. The mine hoist system has complex structure,large inertial mass,high speed, and the work condition usually converts alternately, so it is hard to control it. The mine hoist have some protection measure, so as to promotes the reliability of the machine, people have made many improvements in machine, electronics, maintenance, management...etc. But the bad environment condition including dust, water and whereabouts weights hit result in the damage of various machine spare parts and the electricity component, and the mistakes of the operation and research limitation of travel monitoring system, make the existing protection can not meet expectation, that is why the accident of the mine hoist system have occurred from time to time. Once the hoist route out of control, not in accordance with a given velocity curves, it will result in overspeed and overwind accident, may cause damage to the mine's normal production, even make rope fell continuously and do damage to containers crashes and mechanical and electrical equipment, causing heavy casualties and equipment accidents. This has caused great economic losses to coal production.It shows that route and speed monitoring is the key to preventing serious accidents. At present, however, most of the domestic moist use mechanical device to show the container position and velocity, but the accuracy of such equipment is not high, accidents because of the bad reliability occurred from time to time, all of these does not fit the development and safety requirement of the mining industry. Therefore, the development of precise mine hoist monitoring system is an urgent issue.Based on the coal industry situation, passing the comprehensive analysis to the function of the mine hoist monitoring system, we put forward the intact design project in the paper, improving anti-jamming capabilities of the monitoring system, so that it can be used in bad environment. In the system we use Industrial micro-controller AT89C52 as the main processor and modular design method. The hardware structure is made up of sensor signal input module, CPU module, button module, Relay driver modules, serial communication modules and power module. Many measures are used to increase the anti-jamming capability and stableperformance of the system. The system detect the pulse of each sensor and put it into the main processor after opto-isolated for analysis, judgment, and show the results. When accident such as speeding, cage block, rope loose, depth indicator malfunction, brake space occurred in the process of upgrading, the main processor control safety circuit relay to do security braking. When the container comes to the slowdown point, the main processor control deceleration circuit relay to do deceleration control. Parameters such as depth, the depth factor deceleration distance, slowdown switching and terminal location, speed limit, time and other parameters can be put into the system through the keyboard, these parameters are stored in the EEPROM memory. When accident occur, record about the accident such as the reason and the time of the accident, the location of containers and the upgrade direction are stored, to facilitate the production management and malfunction analysis. Due to the memory capacity constraints, we increase design asynchronous serial communication functions with computer in the design, we can transmit the accident record to the computer database periodically, in which we can backup, archive, inquire and print these record. These functions are not available in the current systems of its kind.In order to achieve accurate monitoring of the speed of the hoist, and upgrade existing machine speed protection methods, a new speed protection method of delayed-type was put in the design, it is based on the dynamic characteristics analysis of the hoist and control system of the braking performance. This new speed protection methods can not only avoid hoist free taxiing deceleration phase of the possible speeding phenomenon and unnecessary speed protection, but also offset the response delay of mechanical and electrical braking system and help them to perform their normal braking effect . It has proved that delayed-type speed protection can achieve accurate and reliable speed protection, and this method is simple and easy to use.Testing of the functions of the monitoring system of mine hoist include two phases. Firstly, we use home-made device and simulator to do software testing and hardware debugging, to verify the reasonableness of system hardware and if the software design meets functional requirements. Later we install the system and do commissioning in mine production site. The testing results show that the overall performance of the monitoring system meet the design requirements.The design of the mine hoist monitoring system can meet the basic needs of mine production. This studying experience will be the basis for improving the system, add additional monitoring functions.