液压凿岩机双缓冲系统性能参数优化设计

针对以往分析凿岩机入射应力波为定值的情况，基于应力波在不同介质中传递原理，计算经过多次透射和反射到达缓冲活塞的应力波大小，并运用傅里叶级数推导入射应力波模型.采用应变片实验法测试入射应力波波形，依据实验结果对入射应力波模型进行修正.基于牛顿力学理论，构建双缓冲系统的蓄能器等效刚柔耦合模型和双缓冲机构模型.借助Matlab工具，分析缓冲活塞运动规律以及一、二级缓冲腔压力变化规律.采用多目标优化方法对双缓冲系统的性能参数进行优化，获得双缓冲系统性能参数的最优参量：缓冲流量8.5 L·min-1、环形间隙0.017 mm、蓄能器初始充气压力2.3 MPa以及工作压力7.6 MPa.

Optimal design of performance parameters for the double damping system of a hydraulic rock drill

For the case of constant stress wave input in analyzing a hydraulic rock drill, the value of stress waves which arrived the damping piston was calculated after many transmissions and reflections. Based on the transfer principle of stress waves in different media, a variable input model was deduced by the Fourier transform. The stress wave forms were tested by using a strain gauge and the variable input model was revised according to the test results. An equivalent rigid-flexible model of the accumulator and a structure model of the double damping system were established based on Newton’ s theory. The damping piston movement laws and the pressure change laws of order 1 and order 2 damping chambers were analyzed. The performance parameters of the double damping system were summarized and optimized by a multi-objective optimization method. The optimized results show that the flow of the damping system is 8. 5 L·min-1 , the annular clearance is 0. 017 mm, the inflation pressure of the accumulator is 2. 3 MPa and the working pressure is 7. 6 MPa.