for drug delivery, chemical analysis and biological sensing
tubes for pressure differential measurements
Micro-hydraulic technology is crucial to the design of micropumps for applications including drug delivery, chemical analysis and biological sensing. Micropumps are classified as mechanical or non-mechanical pumps. Piezoelectric actuated pumps are a mechanical design which has dominated reciprocating micropump technology because of its fast response time and precise dosage ability. However, this is a low efficiency pumping mechanism. Due to the importance of volumetric efficiency in microscale applications, the low efficiency pumping effect is exaggerated in micropumps. Without dramatic improvements in pump efficiency, miniaturization will not be feasible.
Electro-rheological (ER) pumps are non-mechanical micropumps which resolve the low efficiency problem of piezoelectric actuated systems. This technology is especially effective in the low pressure differential and low flow rate regime. Utilizing this regime, the invention enables high efficiency and dynamic response micropumps. By applying an electric field to the ER fluid, dipole interactions between constituent particles are dramatically increased. Varying the applied electric field then generates a flow, enabling low pressure, high efficiency hydraulic pumping. Embodiments of this system include a variant for pressure differential measurement via pitot tubes.
efficiency pumping enables miniaturization of pumps
use of low shear stress behavior and dynamic response of ER fluid