Ejecting ink using shape memory alloys

Abstract

This patent describes ink jet printing device that utilises a shape memory alloy such as a nickel titanium alloy for ejecting drops. The ejection involves utilisation of the transformation of a shape memory alloy from its martensitic phase to its austenitic phase (or visa versa) as an actuator to cause the ejection of ink from the the chamber. The actuator is normally in its quiescent state and transfers to an ink injection state upon heating thereby causing ink ejection from the chamber. The heating occurs by passing a current through the shape memory alloy. The shape memory alloy can be conductive and arranged in a serpentine form for operation. The actuator being formed above a crystallographically etched nozzle chamber having a nozzle port from which ink is ejected.

Dependencies are inferred from the claim text.