| 摘要 |
PROBLEM TO BE SOLVED: To provide a liquid injection apparatus capable of preventing leakage of ink regardless of the mounting position of an ink cartridge, by controlling the air pressure inside the ink cartridge. SOLUTION: In the liquid injection apparatus, a pressure control tube 25 communicating with the inside of the ink cartridge 20 is connected to the pressure control unit 26, while the pressure control tube 25 is connected to a pump 31 inside the pressure control unit 26 via a pressure control valve 29. A pressure sensor 28 can detect the air pressure within the pressure control tube 25, namely within the ink cartridge 20. A control circuit 27 controls the pressure control valve 29 and the pump 31 based on the detection signal sent from the pressure sensor 28, keeping the air pressure within the ink cartridge 20 negative. COPYRIGHT: (C)2005,JPO&NCIPI |
