Patent ID: 6505924
Filing Date: 2003-01-14
Classification: B41J

Abstract:
An ink cartridge for use with a hollow ink extracting needle, ink in the ink cartridge being supplied to a printing mechanism having at least one ink ejecting nozzle, the ink cartridge comprising:a flexible ink pack that contains liquid ink, the flexible ink pack having at least two opposing sheet walls; a housing that houses the ink pack and is box shaped; an ink extracting portion provided at a side surface of the housing, into which the hollow ink extracting needle is inserted to extract the ink from the ink pack housed in the housing; and first and second cantilever plate springs independently provided so as to dispose the ink extracting portion therebetween, each first and second cantilever plate springs having at least one cantilevered portion being cantilevered in the housing and at least one fixed portion being respectively fixed at said at least two opposing sheet walls of said flexible ink pack to urge/pull said at least two opposing sheet walls to opposite directions so that the volume of the ink pack is enlarged, wherein the first and second cantilever plate springs add negative pressures to the ink in the ink cartridge so as to form an appropriate concave meniscus in the nozzle opening for good print quality until the first and second cantilever plate springs are substantially close to the hollow ink extracting needle and the ink in the ink cartridge is almost emptied.