Patent ID: 6776476
Filing Date: 2004-08-17
Classification: B41J,B42D,B82Y,G03B,G06F,G06K,G06T,G07F,G09G,G11C,H01L,H04N,H05K,Y10T

Abstract:
A printhead chip for an inkjet printhead, the printhead chip comprisinga wafer substrate that incorporates drive circuitry, the wafer substrate defining a plurality of ink inlet channels; and nozzle arrangements positioned on the wafer substrate, each nozzle arrangement comprising a passive nozzle chamber structure that extends from the wafer substrate and bounds a respective ink inlet channel; a dynamic nozzle chamber structure that, together with the passive nozzle chamber structure, defines a nozzle chamber, and has a roof that defines the ink ejection port, the dynamic nozzle chamber structure being displaceable towards the wafer substrate into an actuated position and away from the wafer substrate into a rest position such that a drop of ink can be ejected from the ink ejection port, and an elongate micro-electromechanical actuator connected between the wafer substrate and the dynamic nozzle chamber structure, the actuator including a beam assembly that has an active beam of a conductive material, capable of thermal expansion, that defines a heating circuit and is connected to the drive circuitry and a passive beam that is interposed between the active beam and the wafer substrate such that, when the active beam receives an electrical signal from the drive circuitry, the active beam expands relative to the passive beam driving the dynamic nozzle structure into the actuated position to generate the drop of ink and when the signal is cut off subsequent cooling of the active beam causes the dynamic nozzle structure to move back to the rest position, facilitating a separation of the drop of ink.