| Mining dump truck is a special dump truck used to transport coal, sand or other materials off highway in the wild field, such as large open-pit mine and water conservancy projects. Mining dump truck is demanded with safety, reliability and flexibility owning to its large weight, high speed and more curves and slopes in mining area. With the high-speed steady development of the national economy and burgeoning construction of large open-pit mine, the demand for mining dump truck as the main transport machine is increasing sustainably and rapidly. As the main operation of open-pit mine production equipment, mining dump truck has decades of development history abroad. However, there still exist some problems in China such as backward manufacturing technology, poor test and mass production ability, less independent research and development capability, low degree of localization and relatively lagging scientific research, thus seriously restricting the development of the domestic mining dump truck industry despite certain technology level and scale. In this paper, based on actual company projects and combined with the problems arising from the prototype experiments, 100t-mining dump truck will be developed with independent intellectual property, and pointed profound research will be undertaken on accumulator charging system, the performance of hydraulic braking system and lifting control system, which is of important theoretical guiding significance and practical application value. The contents of this paper are summarized as follows:(1)Mining dump truck is overall designed, and the key structure and system performance parameters are calculated. Key structure and key technology of the truck are analyzed and studied from three perspectives, mechanical structure, hydraulic control system, and CAN bus and the J1939 bus collaborative control electrical control system.(2)Charging system is designed based on multi accumulator coupling and system principle is analyzed. The mathematical model of the system charging process is established. Pilot unloading valve of the key components in this system is studied; the principle structure and its features were analyzed. Simulation model of coupling of the accumulator charging system is set up and the effect of system parameters on system performance is studied. The field experiments show that this system has good operation, stable performance, which meets the design requirements.(3)The influence factors of vehicle braking performance are analyzed; computing method of the vehicle brake system brake pressure distribution relationship is put forward through the ideal braking force distribution relationship and vehicle parameters; ideal pressure distribution of front and rear brake hydraulic system value is obtained. Dynamic mathematical model of braking process is established and simulated by applying Matlab/Simulink system. Rear brake is optimized through pressure control mode, and the system principle and design parameters of pressure control valve group are analyzed after optimization. Braking synchronicity test under different back pressures and the optimized real vehicle test show the validity and rationality of design pressure control valve group.(4)The working principle of lifting multistage hydraulic cylinder is analyzed and its mathematical model and AMESim simulation model are established. Proportional control scheme based on the load sensitive electro-hydraulic is put forward and hierarchical control method based on fuzzy control is proposed through shock and vibration problems during the multi-stage changing at level. The lifting system of the whole joint simulation model is established according to the principle of collaborative simulation. The correctness of the simulation analysis and control effect of two kinds control mode are validated through comparing the pressure signal of the field experiment on the handle and section under the control of light and heavy lifting.(5)Vehicle hydraulic system test scheme is designed for testing the performance of hydraulic system of rigid mining dump truck. The data of each subsystem in the vehicle hydraulic system under all kinds of conditions is collected and analyzed including the hydraulic system of hydraulic braking system, steering, wet disk brake cooling hydraulic system, based on which the reliability and rationality of the hydraulic system design are tested. |
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