A new type valveless hydraulic impactor was proposed，and its structure, operational principles and characteristics were analyzed. The mathematical models of return stroke and impact stroke were established respectively. By means of AMESim, the simulation model was obtained and the dynamic simulation was carried out. The influence of the providing flow rate and the initial pressure of the nitrogen chamber on the working performance was studied. While the initial pressure of the nitrogen chamber is constant, the hydraulic impactor will be started only the providing flow rate reaches to a certain value. And in certain limits, the providing flow rate which can make the impactor works under the best performance is found. And when the providing flow rate is constant, the impactor energy and efficiency are low while the initial pressure of the nitrogen chamber is rather low; but when the initial pressure of the nitrogen chamber is too high, the impactor cannot be started. Through the simulation, a conclusion is reached: the impactor working performance is the best when the providing flow rate is 75L/min and the initial pressure of the nitrogen chamber is 2.0MPa. The above work can make the hydraulic impactor design become more exact and proper.

提出一种新型无阀控自配流液压冲击器，分析了它的结构原理及特点。分别建立了冲击器回程和冲程时的数学模型;运用AMESim建立仿真模型并进行动态仿真，根据仿真曲线详细分析了系统供液流量及氮气腔初始充气压力对冲击器工作性能的影响。结果表明：在氮气腔初始充气压力一定时，供液流量必须达到一定值才能启动冲击器，在一定范围内，会出现使冲击性能最佳的流量值;当供液流量一定时，氮气腔初始充气压力较低时，冲击能和冲击效率较低;充气压力过高时，冲击器无法开启。该冲击系统在供液流量为75L/min、氮气腔初始充气压力为2.0MPa时，冲击性能最佳。

无阀自配流液压冲击器, 数学模型, AMESim, 动态仿真