Design of high functional ring type PZT for micropump by using FEM analysis

Recently, micropump for liquid transportation is researched actively. However, the existing micropump is separated into flow part and pump part. The miniaturization of device is difficult, since the designing of flow part is too complex. Therefore, we developed tube type micropump which is the integration of flow part and pump part. This micropump consists of several ring type PZTs in equal intervals on the hollow tube. By adding AC voltage to the PZTs, the PZTs vibrates, and the vibration of PZT is transmitted to the liquid in the hollow tube. Therefore, tube type micropump can transmit liquid. However, flow rate of the tube type micropump is extremely few. Thus, it is necessary to improve fluid performance by increasing deformation amount of PZT actuators. The increasing deformation amount of PZT by adding rectangle trenches is confirmed under FEM analysis. However, according to Static piezoelectric analysis, the stress concentration occurs at the trench part. Therefore, we search for the optimum trench shape which can scatter the stresses while maintain the deformation amount of PZT by static piezoelectric analysis. We focused on (a) existing rectangle trench, (b) trapezoid trench, (c) curvature trench and they were analyzed. As a result, the reduction of equivalent stress is confirmed by changing trench shape from rectangle to other trench shape. However, deformation amount of PZT was decreased by changing trench shape from rectangle to other trench shape. Therefore, it is necessary to search the optimum trench conditions. Recently, micropump for liquid transportation is researched actively. However, the existing micropump is separated into flow part and pump part. The miniaturization of device is difficult, since the designing of flow part is too complex. Therefore, we developed tube type micropump which is the integration of flow part and pump part. This micropump consists of several ring type PZTs in equal intervals on the hollow tube. By adding AC voltage to the PZTs, the PZTs vibrates, and the vibration of PZT is transmitted to the liquid in the hollow tube. Therefore, tube type micropump can transmit liquid. However, flow rate of the tube type micropump is extremely few. Thus, it is necessary to improve fluid performance by increasing deformation amount of PZT actuators. The increasing deformation amount of PZT by adding rectangle trenches is confirmed under FEM analysis. However, according to Static piezoelectric analysis, the stress concentration occurs at the trench part. Therefore, we search for the optimum trench shape which can scatter the stresses while maintain the deformation amount of PZT by static piezoelectric analysis. We focused on (a) existing rectangle trench, (b) trapezoid trench, (c) curvature trench and they were analyzed. As a result, the reduction of equivalent stress is confirmed by changing trench shape from rectangle to other trench shape. However, deformation amount of PZT was decreased by changing trench shape from rectangle to other trench shape. Therefore, it is necessary to search the optimum trench conditions.