Parameters optimization design of air-liquid-combined impact pickaxe

Parameters optimization design of a new light air-liquid-combined impact pickaxe is proposed in this paper, which contributes to an outstanding performance of impact pickaxe. Firstly, kinetics analysis of impact pickaxe with three-segment method was made and kinetic equations were established to simplify abstract problems to mathematical models. Secondly, mathematical optimization models were established to solve the multi-objective optimization design problems; In which, design variables, such as, initial volume and pressure of nitrogen chamber, action area of piston rod, resistance coefficient of piston and working pressure are fully concerned to make objective functions of energy and flow minimum. Thirdly, a nonlinear dynamic model of the hydraulic pickaxe was established, a best stroke process was gotten with improved Euler method. Finally, the optimization parameters of impact pickaxe was determined, which is of small size, high performance. Besides, impact points experiment are used to testify impact performance of pickaxe. After repeated impact tests, impact energy date was ascertained by 58J, which is slightly smaller than theoretical value, but right and reasonable compared with the theoretical value.