Designing a Valveless Micropump

Abstract

Up to the present, the manufacture of the micropump generally used MEMS processes to obtain micro scale channels. However, the geometry of the channels is usually 2.5D and the cost is relatively high due to the characteristics of the most micro fabrication techniques. In this research, we focused on manufacture of three-dimensional valveless micropumps in inexpensive approach. The design of the micropump consists of three horizontal inlet channels and one vertical outlet channel. The 3D geometry of the channels with minimum width of 80 μm gives great challenges in fabrication and is difficult to be achieved by traditional micro fabrication techniques. Shape deposition manufacturing (SDM) process, a layered manufacturing technique involving repeated material deposition and removal, was used to manufacture the chamber and channels of the micropump. CAD/CAM software was applied to slice the 3D model and plan the manufacturing sequences. The piezoelectric buzzer was attached to the fabricated valveless micropump chamber to test the performance. Three different channel width designs were manufactured successfully and tested at various piezo-triggered frequencies. This research provides a solution to manufacture the three-dimensional micropump geometry inexpensively. SDM process was proved to be a suitable approach to generate pre-assembled valveless micropump structure with micro channels, and is applicable to other similar applications.