| 摘要 |
PROBLEM TO BE SOLVED: To set pressure of both tanks to a target pressure value promptly with a simple structure and adjust accurately the pressure to the target pressure value with high followability even when the pressure deviates from the target pressure value.SOLUTION: The inkjet printing device comprises: an inkjet head 11 having nozzles that discharge ink; a pressurized tank 21 that stores ink to be supplied to the inkjet head 11; a negative pressure tank 24 that stores ink returned from the inkjet head 11; a circulation passage that circulates ink from the pressurized tank 21 through the inkjet head 11 to the negative pressure tank 24; an ink pump 25 that feeds ink from the negative pressure tank 24 to the pressurized tank 21; a pressurized pump 52 that adjusts pressure of a gaseous layer part of the pressurized tank 21; a negative pressure pump 56 that adjusts pressure of a gaseous layer part of the negative pressure tank 24; an air passage 62 that connects the gaseous layer part of the pressurized tank 21 to the gaseous layer part of the negative pressure tank 24; and an open/close valve 59 that opens and closes the air passage 62.SELECTED DRAWING: Figure 2 |
