Abstract:The broken belt catch system driven by hydraulic motor was improved and the gear speedincreased device was applied.The model of the new broken belt catch system was established based on hydraulic simulation software AMESim.The system with gear speedincreased device and without gear speedincreased device was simulated and analyzed.The effects of motor displacement, motor rated speed and first gear ratio on dynamic response of system were researched.The results show: the gear speedincreased device makes the maximum displacement and speed of wedge block increase, which improves the energy release capacity of accumulator; with the increase of motor displacement, the maximum displacement of wedge block decrease, the maximum speed of wedge block and the released energy of accumulator increase first, then decrease slightly, but the effect of motor rated speed on system performance is little; with the increase of first gear ratio, the maximum displacement of wedge block decrease, the maximum speed of wedge block and the released energy of accumulator increase.