| Multi-rope friction hoists are used widely in coal mine recently. But its maintenance, especially rope changing has been a puzzle because of complex processing and high risk. This subject has studied the present state of rope changing in and outside the country, including the processing and device of rope changing, and introduced a new method using fast rope-changing device ;The structure and the principle of the device have been detailed described and analyzed and electronic control system and hydraulic system have been designed; Simulation and study of key parts are carried out based on Virtual Prototype technology; Application of Virtual Prototype in device has been explored; Rope changing effect and reliability has been verified, providing reference and basis for further optimization.Rope changing processing is complex. Common method needs much more person, and prone to accidents. This device has a pinch device to avoid rope running, and two clamping devices to carry out stepping rope-changing, exchanging the control and insurance of rope-changing process. Because hydraulics system has advantages of small size, light weight and flexible simple operation, the rope changing system uses hydraulic pressure as its driving force. Electronic control system applied PLC programming realized automatic control, and uses the monitoring signal of rope speed and system pressure to carry out close-loop control.In order to research the device, 3D model of complete system has been built in Pro/E and rope changing process animation is made to check its action in work. Through researching data exchanging between Pro/E and mechanic dynamic simulation software ADAMS, pinch device and clamping device in Pro/E are imported in ADAMS successfully. Added loads and force, virtual prototype was established. Parametric boundary conditions are set as actual work condition. By simulation, dynamic research was carried out to virtual prototype, and simulation result has been analyzed. Finally, the impact of relevant parameters is definite, and the reliability of device is tested.In addition, the subject studied the linkers of clamping device using finite element method. According the simulation result, stress analysis of linkers has been done in Natran. Based on the analysis, the weakness and optimization proposals are given.After test, this set of rope changing system is well used in coal mine. It reduced the difficulty of rope changing, at the same time improved the efficiency and reliability. The method using virtual prototype technology in mechanical design can be widely used in design and manufacture of other Machinery. |
