Ink is filled in an ink cartridge having a housing communicating with ambient air through an air communicating hole, a porous member impregnating with ink, an ink supply port, and a valve device including a valve body always urged by a spring and a valve seat abutting against the valve body, and ink...http://www.google.com.au/patents/US20010052370?utm_source=gb-gplus-sharePatent US20010052370 - Method of filling an ink cartridge with ink and an apparatus thereof
