Patent ID: 6994424

Claim:
An printhead assembly which comprises an ink storage structure connectable to an ink supply arrangement; a manifold mounted on the ink storage structure to receive ink from the ink storage structure, the manifold defining a printhead chip mounting formation and a plurality of ink outlets opening at the mounting formation; and an array of printhead chips positioned in the mounting formation, each printhead chip comprising a wafer substrate that defines a plurality of ink supply passages in fluid communication with the ink outlets; a plurality of nozzle chamber structures positioned on the wafer substrate, each nozzle chamber structure defining a nozzle chamber in fluid communication with an ink supply passage and an ink ejection port in fluid communication with the nozzle chamber; a plurality of control logic and associated power transistor circuits positioned on the wafer substrate; a plurality of elongate actuators fast at one end to the substrate and connected to respective control logic and associated power transistor circuits to receive electrical signals from the circuits to be displaced relative to the substrate on receipt of such signals; and a plurality of ink ejection members positioned in respective nozzle chambers and connected to opposite ends of respective actuators such that displacement of the actuators results in the ejection of ink from respective ink ejection ports.