| 摘要 |
PURPOSE:To detect the presence of an ink cartridge and the residual amount of the ink in a sub-tank by one optical sensor, by detecting the residual amount of the ink in the sub-tank by an optical sensor of which the position is changed over by the presence of the ink cartridge. CONSTITUTION:A sub-tank 9 is provided to a carriage 4 and a float 14 moving up and down according to the residual amount of the ink is arranged in said sub-tank 9 and a shield plate is incorporated in said float 14. An optical sensor consists of a light emitting diode 12 and a light receiving element 13 and a shaking member 16 is made rotatable around a shaft 15. When a ink cartridge 10 is absent, the shaking member 16 reaches a broken line position and light is transmitted from the diode 12 to the light receiving element 13 to be checked. When the cartridge is present, the shaking member 16 reaches a solid line position and the up-and-down position of the shield plate in the sub-tank 9 is detected by sensor to check the residual amount of the ink in the sub-tank. |
