Three-Ports Micro ER Valve for ER Suspension Fabricated by Photolithography

Abstract

A three-ports micro ER valve has been fabricated by photolithography, which is made of a patterned resist film between two-glass plates coated ITO electrode pattern. And one inlet channel (height h 1/4 0.1 mm, width w 1/4 2 mm) of the ER suspension diverges into two outlet channels having ER valves, so that the inflow of the ER suspension from the inlet port is divided into two outflows to the two outlet ports by synchronously controlling a pair of ER valves installed in the outlet channels. The PWM control strategy is applied to a pair of ER valves to change the flow rates, as proposed in our previous paper. The PWM control of each outlet micro ER valve can realize the almost same changing characteristics of flow rate with the duty ratio as that of a conventional valve. The switching characteristics of a pair of ER valves have been investigated by measuring the flow rates from both outlet ports and visualizing the micro-flow behavior of ER suspension in the ER valves.

Electrorheological-fluid-based microvalves

“…Micro-ER valves made with silicon and glass have been reported by Yoshida et al 8 Nakano et al 9 tested ER effects in SU-8 channels with indium tin oxide electrodes. However, these valves are designed mostly to control the flow of ER fluid itself, with two-port valves.…”