Patent ID: 7134740

Claim:
A pagewidth inkjet printhead assembly which comprises an ink supply assembly that spans a print medium, in use; printhead segments that are mounted on the ink distribution assembly to span the print medium, in use, each segment comprising a substrate that defines a number of ink inlet channels, each inlet channel being in fluid communication with a corresponding ink supply assembly; and a plurality of micro-electromechanical nozzle arrangements positioned on the substrate, each nozzle arrangement comprising nozzle chamber walls that define a nozzle chamber in fluid communication with an ink inlet channel, and an ink ejection port, in fluid communication with the nozzle chamber; an elongate actuator tat is anchored, at one end, to the substrate so as to define a suspended arm within the nozzle chamber, a free end of the elongate actuator being displaceable with respect to the substrate on receipt of an electrical current; and an ink ejection member fast with the free end of the actuator and positioned in the nozzle chamber such that the ink ejection member acts to eject ink from the nozzle chamber when the actuator is displaced, wherein drive circuitry for each actuator is interposed between the actuator and the substrate to supply the actuator with said electrical current and to control operation of the actuator.