Patent ID: 7926923

Claim:
An inkjet printer comprising: a main tank that holds ink; a sub-tank unit including a sub-tank; an ink supply mechanism including an ink absorber; and a printhead unit including a printhead for ejecting ink onto a sheet; and wherein the ink supply mechanism connects the main tank to the sub-tank, so as to supply ink from the main tank to the sub-tank; wherein the sub-tank unit is mounted on the printhead unit and supplies ink to the printhead; wherein the main tank and the sub-tank are configured so as to be disconnected from each other via the ink supply mechanism when ink is not being supplied from the main tank to the sub-tank; wherein the main tank and the sub-tank are configured so as to be connected to each other via the ink supply mechanism when ink is being supplied from the main tank to the sub-tank; wherein, when ink is not being supplied from the main tank to the sub-tank the ink absorber is positioned in the ink supply mechanism such that the ink absorber absorbs ink from the sub-tank; wherein, when ink is being supplied from the main tank to the sub-tank, the ink absorber is positioned in the ink supply mechanism such that the ink absorber presents less resistance to ink flowing through the ink supply mechanism into the sub-tank than when ink is not being supplied from the main tank to the sub-tank; wherein the ink supply mechanism further comprises: a connection port that connects to the main tank when ink is to be supplied from the main tank to the sub-tank; an ink path extending from the connection port to the sub-tank; and a retracting mechanism; wherein, when ink is not being supplied from the main tank to the sub-tank, the ink absorber is disposed in the ink path such that the ink absorber absorbs ink from the sub-tank; wherein, when ink is supplied from the main tank to the sub-tank, the retracting mechanism is configured to retract at least a part of the ink absorber away from the ink path.