Liquid-feeding device and liquid ejection apparatus

摘要

There is provided a liquid-feeding device with large liquid-capacity and a simplified structure and capable of stably holding liquid without leakage. An ink-feeding device includes an ink reservoir; an ink chamber; a valve displaced so that a closing member opens an open region by reduction in pressure due to reduction in the ink amount in the ink chamber; a fresh-air communicating hole for communicating with fresh air; and an air inlet tube capable of bringing air, when an amount of ink in the ink chamber is reduced, from the fresh-air communicating hole by the amount of air corresponding to the amount of the reduced ink, wherein a bore diameter of the lower end of the air inlet tube and a water head are determined so that the ink meniscus holding power P at the lower end of the air inlet tube and the water head pressure H corresponding to the height from the bottom surface of an ink ejection unit (nozzle surface) to the lower end of the air inlet tube satisfy the relationship P>H.