A miniature circular pump with a piezoelectric bimorph and a disposable chamber for biomedical applications

Abstract

Piezoelectric miniature pumps provide excellent stability and accuracy, and thus, have been used in fluid handling and medical applications. In the current study, a separable piezoelectric miniature pump was developed by combining a piezoelectric bimorph actuator and a disposable pumping chamber. By employing a single-use disposable pumping chamber the cross-contamination issues caused by repeated uses of the pumping chamber can be easily avoided, making the pump ideal for biological fluid transmission process. The pumping in the proposed miniature pump was indirectly driven by a circular piezoelectric bimorph actuator through a pillar structure that connects the actuator with the covering PET diaphragm of the pumping chamber. The pumping efficiency of the proposed miniature pump was investigated with respect to several parameters, such as the diaphragm thickness, the chamber diameter and the pillar-to-chamber ratio. A maximum flow rate of 9.1mL/min was achieved by using the proposed pump structure with 10mm chamber diameter and a pillar-to-chamber ratio of 0.9.