HEAD CHIP AND HEAD UNIT HAVING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a head chip and a head unit having the same capable of preventing occurrence of defective ejection due to bubbles. SOLUTION: This head chip comprises a piezoelectric ceramic plate 11 having a plurality of grooves 12 each being opened in one face and in one end face facing the lower section in the vertical direction, an ink chamber plate 17 which is bonded to the one face of the piezoelectric ceramic plate 11 so as to close the openings of the grooves 12 and has a demarcated ink chamber 21 which communicates with the grooves 12 and a nozzle plate 25 which closes the one end face and has nozzle openings 27 respectively corresponding to the grooves 12. A driving voltage is applied to an electrode 15 provided to a side wall in the groove 12 and a volume in the groove 12 is varied so that ink filled in the groove 12 is ejected from the nozzle opening 27 downward in the vertical direction. The groove 12 and common ink chamber 21 are provided such that positions of the top ends of both of them are roughly the same, thereby preventing the bubbles from remaining in the grooves 12.