INK JET HEAD AND INK JET DEVICE EQUIPPED WITH THE SAME

摘要

PROBLEM TO BE SOLVED: To provide an ink jet head in which discharge stability owing to circulation of ink and reduction in ink material loss are compatible; and to provide an ink jet device equipped with the ink jet head.SOLUTION: An ink jet head includes: an ink supply flow passage 101 to which ink is supplied through an ink introducing port; an ink discharge flow passage 102 from which ink is discharged to an ink collecting port; ink chambers 110 through which the ink supply passage and the ink discharge flow passage are communicated with each other and which each have at least one nozzle to discharge ink; and actuators displacing oscillation plates 130 in the ink chambers to apply pressure on the ink in the ink chambers. The ink jet head is characterized in that a minimum opening length at the flow passage cross-section at the nozzle downstream side is smaller than the minimum opening length at the flow passage cross-section at the nozzle upstream side.