| 摘要 |
PROBLEM TO BE SOLVED: To eliminate waste of paper or ink by detecting the residual quantity of ink in an ink tank based on the weight of residual ink. SOLUTION: Weight of ink in an ink tank 2 decreases as the residual quantity of ink decreases through printing and the ink tank 2 is lifted by the spring force of a spring 7 while turning about a pin 6a, as a fulcrum. Consequently, the bottom part 2b is separated from a proximity sensor 8. When the separating operation is sensed by the proximity sensor 8, ink is supplied from an ink supply passage 4 into the ink tank. When the ink tank is fully filled with ink again, the ink tank 2 descend while turning and the bottom part 2b approaches the proximity sensor 8. When the approaching operation is sensed by the proximity sensor 8, ink supply from the ink supply passage is interrupted. |
