Nozzle arrangement for an inkjet printhead having dynamic and static structures to facilitate ink ejection
View Patent ↗Provided is a nozzle arrangement for an inkjet printhead. The nozzle arrangement includes a substrate with side walls and a roof portion together forming an ink chamber, the substrate defining an ink supply channel leading to the ink chamber, with one side wall defining an aperture. The arrangement also includes an elongate actuator extending through said aperture into the ink chamber, as well as a dynamic structure cantilevered from the side wall below the aperture. Further included is a static structure cantilevered from the side wall below the dynamic structure. The actuator is connected to the dynamic and static structures at a point distal from the aperture such that thermal expansion of the dynamic structure moves the actuator upwards in the chamber to eject ink from the chamber via a port defined in the roof portion.
1. A nozzle arrangement for an inkjet printhead, said nozzle arrangement comprising:
a substrate with side walls and a roof portion together forming an ink chamber, the substrate defining an ink supply channel leading to the ink chamber, with one side wall defining an aperture;
an elongate actuator extending through said aperture into the ink chamber;
a dynamic structure cantilevered from the side wall below the aperture;
a static structure cantilevered from the side wall below the dynamic structure, wherein the actuator is connected to the dynamic and static structures at a point distal from the aperture such that thermal expansion of the dynamic structure moves the actuator upwards in the chamber to eject ink from the chamber via a port defined in the roof portion.
2. The nozzle arrangement of claim 1 , in which the ink supply channel defined in the substrate is the result of a back-etching process carried out on the substrate.
3. The nozzle arrangement of claim 1 , in which CMOS dielectric layers are positioned on the substrate, with CMOS micro-processing drive circuitry being positioned on the CMOS dielectric layers.
4. The nozzle arrangement of claim 3 , in which a metal diffusion barrier is positioned in the dielectric layers about the ink supply channel.
5. The nozzle arrangement of claim 1 , in which the static structure defines a fixed part of the chamber side wall and the dynamic structure defines a movable part of the chamber side wall and the roof which defines the ink ejection port.
6. The nozzle arrangement of claim 5 , in which the movable part of each chamber wall overlaps the fixed part of the nozzle chamber side wall.
7. The nozzle arrangement of claim 6 , in which the fixed part of the chamber side wall defines an inwardly directed lip that extends into the nozzle chamber and an outwardly directed, re-entrant portion that terminates in a radially extending rim, the moveable part depending from the roof portion and terminating at a free edge, so that the re-entrant portion and the free edge can define a fluidic seal when the chamber is filled with ink via the supply channel.