Research On Dynamic Shift Strategy For 32 Tons Mine Dumpers

Heavy Mining Tipper is a class of non-road vehicles used in short-distance transportation. Harsh working condition, heavy and frequently changing loads are the distinguished features of tipper. The application of the automatic transmission technology in the heavy mining equipments can reduce driver’s labor intensity and enhance the working efficiency of the vehicle. At present, the automobile automatic transmission theory is quoted to tipper automatic shifting strategy without taking tipper’s particular working condition into account, which has resulted in some serious problems, such as insufficient power and cyclic shift.Based on automobile two parameters automatic transmission theory and dumper’s working condition, this paper put forward a new parameter——vehicle load coefficient which could represent comprehensive performance of vehicle load and road condition. Finally, a new shift strategy called “Three-Parameters Dynamic Shifting Strategy” was proposed, which selected throttle opening, speed and vehicle load coefficient as shifting control parameters.Taking 32 tons of mining tipper as the research object, this paper built the mathematical model of vehicle transmission system firstly, which included the mathematical model of engine, hydraulic, etc. In this section, the collaborative work situations of engine and hydraulic torque converter were mainly researched, and the collaboration output characteristic curves were solved in the end. Following, the best shift speed points were solved by the analytical method and graphic method, and the optimum shift curves of dynamic shift strategy were given finally.The simulation models of vehicle transmission system were established under the situation of MATLAB/SIMULINK. Various composite conditions simulation tests were operated for the shift strategy in this article. Test results showed that the strategy could adapt to the bad environment and a variety of working conditions, ensure vehicle’s power performance under various situations and reduce the automatic gear patterns settings.A test platform was built and the test was operated on the equipment supplied by a factory. For the shift test this paper needed, a new improved scheme of the test-bench was put forward, a test software and a automatic shifting program was also designed in the end.