Patent ID: 7699439

Claim:
A droplet ejection head comprising: a first laminate having a plurality of nozzles; a second laminate bonded to the first laminate and internally having a plurality of pressure generating chambers communicating with the plurality of nozzles; a plurality of piezoelectric devices having individual electrodes and common electrodes, the piezoelectric devices being provided in the second laminate correspondingly to the plurality of pressure generating chambers, the plurality of piezoelectric devices changing volumes of the plurality of pressure generating chambers in accordance with driving signal supplied to the individual electrodes so that fluid reserved in the pressure generating chambers is ejected as droplet from the nozzles; a first wiring board connected to the individual electrodes and supplying the driving signal to the individual electrodes; and a second wiring board connected to the common electrodes in common, wherein the second wiring board includes a diaphragm that is bent in accordance with deformation of the piezoelectric devices so as to change the volumes of the pressure generating chambers, the individual electrodes are provided on first surfaces of the piezoelectric devices respectively, the common electrodes are provided on second surfaces of the piezoelectric devices respectively, the second surfaces being opposite to the first surfaces, the common electrodes are connected to the diaphragm by adhesive, the diaphragm has an extension portion, the common electrodes of the piezoelectric devices are connected to an earth line through the extension portion, the extension portion of the diaphragm is fixedly attached to a first surface of an external bonding member that introduces the fluid into the droplet ejection head, and a second surface of the external bonding member faces the diaphragm.