Inkjet nozzle device having high degree of symmetry

1. An inkjet nozzle device comprising a main chamber having a floor, a roof and a perimeter wall extending between the floor and the roof, the main chamber comprising:

a firing chamber having a nozzle aperture defined in the roof and an actuator for ejection of ink through the nozzle aperture;

an antechamber for supplying ink to the firing chamber, the antechamber having a main chamber inlet defined in the floor; and

a baffle structure partitioning the main chamber to define the firing chamber and the antechamber, the baffle structure extending between the floor and the roof,

wherein:

the firing chamber and the antechamber have a common plane of symmetry, and the perimeter wall encloses the main chamber and defines sidewalls of the firing chamber and the antechamber.

2. The inkjet nozzle device of claim 1 , wherein the floor and the roof are common to the firing chamber and the antechamber.

3. The inkjet nozzle device of claim 1 , wherein the common plane of symmetry bisects the nozzle aperture, the actuator, the baffle structure and the main chamber inlet.

4. The inkjet nozzle device of claim 1 , wherein the baffle structure comprises a single baffle plate.

5. The inkjet nozzle device of claim 4 , wherein the baffle plate has a pair of side edges such that a gap extends between each side edge and the perimeter wall to define a pair of firing chamber entrances flanking the baffle plate, the firing chamber entrances being disposed symmetrically about the plane of symmetry.

6. The inkjet nozzle device of claim 1 , wherein the nozzle aperture is elongate having a longitudinal axis aligned with the plane of symmetry.

7. The inkjet nozzle device of claim 1 , wherein the nozzle aperture is elliptical having a major axis aligned with the plane of symmetry.

8. The inkjet nozzle device of claim 1 , wherein the actuator comprises a heater element.

9. The inkjet nozzle device of claim 8 , wherein the heater element is bonded to the floor of the firing chamber.

10. The inkjet nozzle device of claim 8 , wherein the heater element is elongate having a longitudinal axis aligned with the plane of symmetry.

11. The inkjet nozzle device of claim 10 , wherein a centroid of the nozzle aperture is aligned with a centroid of the heater element.

12. The inkjet nozzle device of claim 10 , wherein the heater element extends longitudinally from the baffle structure to the perimeter wall.

13. The inkjet nozzle device of claim 1 , wherein the perimeter wall and the baffle structure are comprised of a same material.

14. The inkjet nozzle device of claim 13 , wherein the perimeter wall and the baffle structure are comprised of a material selected from the group consisting of: silicon oxide, silicon nitride and combinations thereof.

15. The inkjet nozzle device of claim 1 , wherein the main chamber is generally rectangular in plan view, and wherein the perimeter wall comprises a pair of longer sidewalls parallel with the plane of symmetry and a pair of shorter sidewalls perpendicular to the plane of symmetry.

16. The inkjet nozzle device of claim 15 , wherein a first shorter sidewall defines an end wall of the firing chamber and a second shorter sidewall defines an end wall of the antechamber.

17. The inkjet nozzle device of claim 1 , wherein the firing chamber has a larger volume than the antechamber.

18. An inkjet printhead comprising a plurality of inkjet nozzle devices according to claim 1 .