Research on Pressure Pulsation Characteristics of Gerotor Pump for Active Vibration Damping System

High response, stable operation, small volume active vibration damping system and other intelligent hydraulic equipment have become the inevitable trend of future development. A compact low-pulsation gerotor pump is designed to meet these requirements, the theoretical flow pulsation of 8/9 tooth gerotor pump is analysed, and its pressure pulsation characteristics are also studied in this paper. The combined pulsation buffer is placed at the bottom valve plate high-pressure port of pumps. High-pressure oil passes through the honeycomb damping hole and enters the diaphragm volume chamber of the accumulator to form a combined pulsation buffer. Considering the effect of the pulsation buffer structure to reduce flow pulsation at different speeds, a test bench for high-speed gerotor pump pulsation characteristics is built, and the pressure pulsation of the gerotor pump with and without pulsation buffer is analysed at different speeds. Results show that the pressure pulsation frequency increases with pump speed. When the speed reaches 5500 r/min, 8/9 tooth gerotor pump without pulsation buffer outlet pressure pulsation reached 13.797% and that with pulsation buffer outlet pressure pulsation decreased to 9.871%, showing a 28.46% decline rate. At pump rotation speeds are 1500 r/min and 2500 r/min, the pulsation reduction ratios are 37.78% and 35.36%. The pressure pulsation of the gerotor pump can be evidently reduced by designing a combined pulsation buffer in this paper. Therefore, this high-speed and low-pulsation gerotor pump is suitable for active vibration damping system and other intelligent hydraulic equipment.