Patent ID: 7488057

Claim:
A piezoelectric ink jet printer head comprising: an actuator comprising an upper upper electrode, a lower electrodes, a piezoelectric plate between the upper electrode and the lower electrodes, a protection layer over the upper electrode, and a resilient plate below the lower electrode; a spacer below the resilient plate, wherein a first portion of the spacer forms sidewalls of a chamber and a second portion of the spacer an upper surface of an ink passage; a channel plate below the spacer, wherein a first portion of the channel plate forms a sidewall of the ink passage under the second portion of the spacer and a second portion of the channel plate forms a sidewall of the chamber; a nozzle plate below the channel plate, wherein a first portion of the nozzle plate forms a bottom surface of the chamber and a second portion of the nozzle plate forms a bottom surface of the ink passage; a nozzle at a bottom portion of the chamber; and a through-hole formed through the actuator and the spacer reaching the ink passage, wherein the through-hole is configured to supply ink to the chamber via the ink passage.