| 摘要 |
PROBLEM TO BE SOLVED: To provide a bubble detector and a bubble detecting method in which presence/absence of a bubble can be judged without influencing a liquid flow and without wasting the liquid. SOLUTION: An inkjet head 2 comprises an ink cartridge 3 and a head body 4. The head body 4 has an ink supply needle 6, an ink supply passage 7 and a detection passage 8. The ink supply passage 7 is filled with ink 9 and fixed with a pressure pump 11. The detection passage 8 is stored with a predetermined quantity of liquid 13. The ink supply passage 7 is provided with a grid hole 7a. The detection passage 8 is fixed with a detection film 14 at a position corresponding to the grid hole 7a. A pressure is applied to the ink supply passage 7 by mens of the pressure pump 11. Level of the liquid 13 in the detection passage 8 varies depending on presence/absence of a bubble (b) in the ink supply passage 7. A water level detector 15 detects variation in the water level photoelectrically and detection results are delivered to a controller 12. The controller 12 judges presence/absence of the bubble (b) based on a photoelectric detection value. COPYRIGHT: (C)2004,JPO |
