Ink printhead nozzle arrangement with thermal bend actuator
View Patent ↗An ink jet printhead nozzle arrangement having an ink chamber formed in a wafer substrate and one wall of the chamber having at least one flexible portion. The ink ejection port is formed centrally on the wall with a rim surrounding it. The wall is adapted to move independently of the rim such that upon heating of the flexible portion of the wall, the wall bends into the ink chamber forcing ink therein out through the ejection port.
1. An ink jet printhead nozzle arrangement comprising:
a wafer substrate
an ink chamber formed therein;
an ink ejection port formed by a substantially centrally located rim on a wall of said chamber; and
at least one flexible portion located on said wall outside of said centrally located rim;
whereby the wall is adapted to move independently of said rim such that upon actuation the at least one flexible portion moves the wall into said ink chamber forcing ink therein, out through the said ink ejection port; and
wherein the said at least one flexible portion of said wall is made from material having a thermal expansion suitable to cause the wall to bend into said ink chamber upon heating of the at least one flexible portion of the wall.
2. The arrangement according to claim 1 wherein a heating element is located in conductive contact with each flexible portion of the wall.
3. The arrangement according to claim 2 wherein the heating element is serpentine in shape to allow for unhindered expansion of the flexible wall portion.
4. The arrangement according to claim 1 wherein an ink inlet channel formed in said wafer substrate and is in communication with said ink chamber.
5. The arrangement according to claim 4 wherein the ink inlet channel enters into said ink chamber opposite the said wall.