Ink jet printer head

An ink jet printer head comprising:

• a cavity plate formed with a plurality of pressure chambers, nozzles, and ink supply sources, the pressure chambers being arranged in at least three columns that extend parallel with each other in a column direction, each pressure chamber being connected to a corresponding nozzle through one end of the pressure chamber and to a corresponding ink supply source through the other end of the pressure chamber, each pressure chamber having a pair of first side walls extending parallel with the column direction, a principal portion of the pressure chamber being defined by the first side walls and two imaginary parallel lines that perpendicularly intersect the first side walls and each principal portion of one column of pressure chambers being arranged so that each principal portion is staggered from the principal portion of the pressure chamber of an adjacent column of pressure chambers;
• and
• an actuator in confrontation with the pressure chambers of the cavity plate, the actuator applying ejection pressure to the ink in the ink pressure chambers.

An ink jet printer head comprising:

• a cavity plate formed with a plurality of pressure chambers, nozzles, and ink supply sources, the pressure chambers being arranged in a plurality of columns that extend parallel with each other in a column direction, each pressure chamber having a substantially parallelogram shape including two acute-angle portions, a through hole connected to the nozzle being formed in one acute-angle portion, a through hole connected to the ink supply source being formed in the other acute-angle portion, the pressure chambers being arranged so that the pressure chambers are shifted out of alignment with each other in a direction extending parallel with the column direction each pressure chamber having a pair of side walls that extend parallel with each other in the column direction;
• and
• an actuator unit disposed across the plurality of pressure chambers and including a plurality of pressure generating portions at positions that correspond to the pressure chambers.

An ink jet printer head comprising:

• a cavity plate formed with a plurality of pressure chambers, nozzles, and ink supply sources, the pressure chambers being arranged in at least three columns that extend parallel with each other in a column direction, each pressure chamber having a substantially parallelogram shape, defined by a pair of first side walls that extend parallel with each other in the column direction and second side walls that extend parallel with each other, each pressure chamber being connected to a corresponding nozzle through one end of the pressure chamber and to a corresponding ink supply source through the other end of the pressure chamber, the pressure chambers being arranged so that the pressure chambers are shifted out of alignment with each other in the column direction;
• and
• an actuator unit disposed across the plurality of pressure chambers and including a plurality of pressure generating portions at positions that correspond to the pressure chambers.