US Patent 7396111 Inkjet head and inkjet printer

An inkjet head including piezoelectric sheets each of which has an individual electrode-forming region on its front surface, and inner electrodes in its inside. Individual electrodes are arranged in the individual electrode-forming region. The inner electrodes are arranged opposite to the individual electrodes. Front surface common electrodes are provided on the front surface of the piezoelectric sheet so that the front surface common electrodes are formed as land portions disposed around the individual electrode-forming region. The front surface common electrodes are formed to extend lengthwise along outer edges of the individual electrode-forming region. One end portion of front surface common electrode in the lengthwise direction is connected to a connection terminal of a board connected to a drive circuit. The other end portion of front surface common electrode is electrically connected to a corresponding inner electrode via through-hole formed below the front surface common electrode.