液压凿岩机配流阀零位开口设计与实验研究

Design and experiment on the opening at zero position of distribute valve of hydraulic rock drill

液压凿岩机配流阀零位正开口设计的定位导向精度要求高,增加了其制造难度,系统内泄量大,降低了凿岩机的工作效率.针对此不足,通过比较分析零位正开口与零位负开口的优点和不足,提出了一种零位负开口的设计方法和零位开口压力增量的计算方法,从蓄能器的耦合和局部阻力角度建立配流阀零位开口的数学模型,得出了阀芯开口运动的非线性方程.利用Simulink对阀芯零位开口进行了运动学仿真,分析对比了不同开口形式对凿岩机冲击性能和系统压力的影响,并与实验结果进行对比,验证了仿真的准确性.结果表明:液压凿岩机配流阀零位负开口设计优化了导向方式,降低了制造难度,其工作效率提高了9.2%,单次最大冲击能提高了12.5%.零位负开口设计的高可靠性和高效率优势更符合实际工况要求.

With the high accuracy requirement of the guide-localization of the distribute valve,the manufacture of the valve is more difficult when the design of positive opening at the zero position is used in the hydraulic rock drill,and the leakage of the drill is larger,which reduces the working efficiency of the hydraulic rock drill.So a design approach to the negative opening at the zero position and a computing method for the pressure increment of it were put forward to solve this problem on the basis of an analysis and comparison of advantages and disadvantages of the positive opening and negative opening at the zero position respectively.The mathematical model of the valve whose opening was at zero position was therefore established based on the coupling of the accumulator and local resistance.Through the mathematical model,the non-linear equation of the opening motion of the core was obtained.The kinematics of the opening motion at zero position of the valve was simulated in Simulink to analyze and compare the influence of different opening types on the impact property and the pressure of the drill.Compared with the experiment result,the simulation result was verified.The results showed that the design of the negative opening at the zero position of the distribute valve of the hydraulic rock drill optimized the way of guide-localization and reduced the manufacturing difficulties,in addition,the working efficiency of the hydraulic rock drill was increased by 9.2% and the impact energy at a time was increased by12.5%.Considering the high reliability and efficiency,the design of the negative opening at the zero position is finally selected to be used in the actual working conditions.