AN INK JET PRINTER, A METHOD OF SHUTTING DOWN THE SAME, A METHOD OF CONTROLLING THE FLOW OF INK TO THE SAME, AND AN INK SUPPLY SYSTEM FOR THE SAME

摘要

An ink jet printer includes an ink supply system for supplying ink through the print head (10) of the printer. The fluid supply system includes a pump arrangement (22) supplying ink to the print head (10) from a supply tank (16) via a fluid supply line (56). A plurality of ink return lines (40, 42, 44) are connected between the pump outlet (26) and the pump inlet (24). Each of the ink return lines includes a flow restriction (46, 48, 50), with the flow restriction in each line providing a fluid flow impedance which differs from the impedances provided by the other flow restrictions. A valve arrangement (52, 54) connects the pump outlet (26) to selected ones of the ink return lines, to provide means for controlling the flow rate of ink supplied through the ink supply line (56) to the print head (10). During periods in which the printer is shut down, a substantially reduced ink flow through the print head is continuously maintained at a reduced fluid flow rate and at a reduced fluid pressure.