In an ink jet recording apparatus, a recording head is mounted on a carriage which reciprocately moves in a widthwise direction of recording paper. A subtank is mounted on the carriage for supplying ink. A main tank stores ink which is replenished to the subtank. An ink amount detector detects an amount...http://www.google.com.au/patents/US20020024543?utm_source=gb-gplus-sharePatent US20020024543 - Ink jet recording apparatus, method of replenishing ink to subtank in the apparatus, and method of checking the replenished amount of ink
