The ink passage houses the ink tank, printhead, caps, maintenance jet tray, maintenance cartridge, waste ink collector, ink tubes interconnecting the mechanical

units, suction pump driven mainly for sucking inks and so on. Its functions include supplying, circulating and sucking inks.

The ink passage (per color) is schematically shown below, along with the ink flow.

Agitation Plate

Air Passage

Subtank Ink Remaining

Detection Needle

a) Supplying inks from the ink tanks to the ink supply valve assembly

The ink tanks each contain ink to feed the printhead.

The ink is supplied from the ink tanks to the subtanks first, then to the ink supply valves.

Air is discharged through the air passage to keep the internal pressure of the ink tanks and subtanks constant.

b) Supplying inks from the ink supply valves to the printhead

The ink stored in an ink tank flows to the printhead when the suction pump is driven with the ink supply valve opened and the head capped.

The ink sucked from the caps flows to the maintenance cartridge.

c) Supplying inks while printing

The ink supply valves and subtank air passage valves are kept open while printing, so that inks is constantly flowing to the printhead under the negative pressure

of the nozzle assembly which is caused by the discharging inks.

Furthermore, waste inks sucked in the cleaning operation and inks from the maintenance jet tray flow into the maintenance cartridge.

If all of ink passages are opened (no ink tank is installed, the ink supply valve is opened, the subtank air passage valve is opened, and the printhead fixer lever is

opened) when the ink tube is being filled with ink, the ink in the ink tube may reverse-flow due to the fluid level difference and ink may leak from the hollow needle

of the ink tank.

Do not open all of the ink passages at the same time when the ink tube is being filled with ink.

d) Agitation of ink in the ink tank

Ink in the ink tank and the subtank are agitated to prevent precipitation of pigment-based ink in the ink tank and subtank.

This function is implemented by reverse-flowing ink to the ink tank and subtank by opening and closing the ink supply valve and subtank air passage valve in

succession. Inside the ink tank is provided with an agitation plate to assist agitation of ink. (The agitation plate is also provided in the dye ink tank.

- Operation timing: When a new ink tank is installed or when 168 hours have lapsed since the previous agitation (the agitation is performed irrespective of the

whether the printer is printing or cleaning its head)

- Ink supply valve opening/closing count: 30 times (every 30 seconds)

If 336 or more hours have lapsed, the ink valve opening/closing count and the time until the next agitation are changed according to the length of the tame lapsed.

Mechanical Drive Unit

Ink Flow

Ink Tank

Needle(air passage)

Needle(ink supply)

Ink Supply

Valve

Air Passage

Subtank Air

Subtank

Passage Valve

Carriage Unit