Simulating a high frequency piezo pump with disc reed valves

Abstract

Piezo pumps provide an attractive alternative for driving small actuators (e.g. less than 100W) compared to traditional valve controlled cylinders powered by a central hydraulic supply. This provides the ability to distribute power electrically rather than hydraulically, which can bring both weight and efficiency savings. Currently the use of piezo pumps is severely limited by the maximum power and flows that can be  provided. This paper documents the simulation of a new pump which makes use of disc type reed valves to rectify the flow generate by a single piezostack-driven piston. The proposed valves have the potential to overcome frequency limitations of more conventional poppet or ball type check valves. This enables the pump to operate at higher frequencies and thereby produce larger flows. Simulation results suggest that a pump capable of producing a no load flow in excess of 1L/min would be possible using an off-the-shelf piezo stack.