| 摘要 |
PROBLEM TO BE SOLVED: To eliminate a movable mechanism coming in touch with ink or the like which possibly contaminates ink by setting a light guide at a position in touch with ink in an ink tank, inputting light to the light guide, receiving an output light, and detecting a quantity of ink from a quantity of received light. SOLUTION: The ink tank is constituted of two chambers, i.e., an absorbing body chamber 1 and a raw ink chamber 2. A light guide 8 shaped like a cylindrical rod erects in the raw ink chamber 2 among the two chambers. At the side of one end of the light guide 8 are set a light-emitting element 9 and a light- receiving element 10 adjacent to each other, and a light-shielding means 11 is set between the light-emitting element 9 and light-receiving element 10. The light-emitting element 9 is turned on and off by a signal of an oscillation circuit. The light turned on, off is detected by the light-receiving element 10 through the light guide 8. A quantity of a raw ink 6 in the raw ink chamber 2 is detected from a quantity of the light received by the light-receiving element 10. |
