Patent ID: 7322680

Claim:
An inkjet printer that comprises a printing mechanism that defines a printing path through which media can be fed so that the printing mechanism can carry out a printing operation on the media, the printing mechanism having a printhead assembly that comprises a printhead with at least one printhead chip that is operatively positioned with respect to the printing path, the, or each printhead chip comprising a wafer substrate; drive circuitry positioned on the wafer substrate; and a plurality of nozzle arrangements positioned on the wafer substrate, each nozzle arrangement comprising nozzle chamber walls that define a nozzle chamber; a micro-electromechanical actuator that is mounted on the substrate to be connected to the drive circuitry and having an actuating portion that bends on receipt of an electrical signal from the drive circuitry and an ink displacement member that is positioned on the actuating portion to extend through a wall of said nozzle chamber into the nozzle chamber, so that, when the actuating portion receives the electrical signal, the ink displacement member is driven towards the ink ejection port to eject ink from the ink ejection port, said actuating portion being disposed outside of said nozzle chamber such that said actuating portion is not in contact with ink; and a protective covering shell positioned on the substrate and defining an enclosure in which the actuator is positioned; and a feed mechanism for feeding media through the printing path.