Pressure generating mechanism, manufacturing method thereof, and liquid droplet ejection device including pressure generating mechanism

摘要

An actuator unit includes piezoelectric ceramic sheets put in layers. Common and individual electrodes are disposed alternately between the piezoelectric ceramic sheets. Each portion of a piezoelectric ceramic sheet where common and individual electrodes overlap each other is a deformable active portion. Each active portion corresponds to a pressure chamber of an ink passage unit. When a drive electric field is applied selectively between common and individual electrodes in a pair, the corresponding active portion is deformed along the thickness direction of the piezoelectric ceramic sheet to change the volume of the corresponding pressure chamber. Microcrack regions provided on both sides of the deformed active portion prevent the deformation of the active portion from propagating to neighboring active portions.