Design and testing of a microvalve capable of precisely controlling low fluidic flow rates

Abstract

Development of the design, manufacture, and testing for a gas flow regulating microvalve is presented herein. The microvalve project served as a test bed for new micromachining techniques and for exploration of MEMS devices made from non-silicon materials. We developed and tested a novel microvalve utilizing a passive mechanical membrane that allows for accurate flow rate control over a wide range of inlet pressures, requiring power only to adjust the flow rate. Design considerations and functional analysis of a microvalve system are discussed, and manufacturing techniques analyzed. The design was verified by comparing the prototyped system to a commercially available mini ball valve. The valves were run through full actuation at varying pressures and the resulting flow was observed and characterized. At 0.69 MPa, the flexure valve prototype was shown to allow adjustments in flow between 1.0* 10-6 and 2.0* 106 m3/s over the period of about 8 seconds, allowing for a precision adjustment of flow not available in other valves. The experiment demonstrates that the new microvalve offers significant advantages in terms of a wider range of flow rate adjustment available within the operating pressure regime.