Fluid Micropumps Based on Rotary Magnetic Actuators

A jet-type magnetically driven fluid micropump to drive conductive fluids has been designed, fabricated, and tested. The pump actuation is based on a rotary magnetic micromotor with fully integrated stator and coils operating with the rotor immersed in the fluid to be pumped, thereby driving the fluid from a inlet flow reservoir through integrated flow channels to an outlet flow reservoir. The micropump has been successfully driven using standard diabetic-prescription insulin in saline buffer (Novo Nordisk, Regular Insulin) as a working fluid, demonstrating the feasibility of a rotary micropump for pumping and injecting fluids in drug delivery or chemical flow systems. The attained flow rate varies monotonically with motor speed. In the realized micropump, the fluid flow rate achieved is up to 24 p!/min at a rotor speed of 5000 rpm. The operating voltage is less than 3 V and the power consbmption is approximately 0.5 W. The differential pressure is expected to be approximately 100 hPa.