Patent ID: 7938514

Claim:
A printing nozzle comprising: a chamber defined over a fluid inlet in a substrate including a non-corrosive dielectric coating/chamber-defining layer and having a fluid ejection port; an actuator for causing ejection of fluid within the chamber from the fluid ejection port comprising an outer arm portion having an end fixed by the non-corrosive dielectric coating/chamber-defining layer, and an inner arm portion connected electrically to a power source that applies a pulsed excitation voltage thereto to result in pulsed current flow through causing the elongation of the inner arm portion; a controller for controlling operation of the actuator by applying a current pulse having a predetermined energy level to the actuator; a sensor for sensing operation of the actuator; and a plurality of posts sandwiched between the inner arm portion and the outer arm portion to mechanically couple but electrically isolate the arm portions so that no current-induced heating occurs within the outer arm portion, wherein the controller applies a current pulse having an energy level significantly greater than said predetermined energy level to the actuator when the sensor senses faulty operation of the actuator.