The ink passage consists of ink tanks, printhead, cap, waste ink collection unit, ink tubes for connecting the mechanical components, and an ink suction pump which

is operated to suck ink. These components are used to supply, circulate, and suck ink.

A schematic diagram of the ink passage (for one color) and the ink flow are shown below.

Agitation plate

Sub buffer

Absorbent material under the ink tank unit

a) Ink supply from ink tank to ink supply valve

The ink tank contains ink to be supplied to the printhead.

Ink flow from the ink tank to the ink tank supply valve due to the fluid level difference.

b) Ink flow from ink tank to sub-buffer

Ink flows from the ink tank to the sub-buffer due to the fluid level difference, and air enters the ink tank through the air passage of the sub-buffer, maintaining the

pressure inside the ink tank constant.

If the ink in the sub-buffer exceeds the predetermined level, the excessive ink flows to the absorbent material under the ink tank.

c) Ink supply from ink supply valve to printhead

Ink is supplied from the ink tank to the printhead by opening the ink supply valve, capping the head, and operating the suction pump.

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

d) Ink supply during printing

During printing, the ink supply vale is held open to allow ink to flow from the ink tank to the printhead constantly due to the negative pressure generated by dis-

charging of ink.

The waste ink used for printhead cleaning and borderless printing flows to the waste ink absorbent materials under the maintenance cartridge and purge unit in

addition to the waste ink box.

If all of ink passages are opened (no ink tank is installed, the ink supply valve is opened, and the printhead fixer lever is opened) when the ink tube is 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 filled with ink.

e) Agitation of ink in the ink tank

Ink in the ink tank is agitated to prevent precipitation of pigment-based ink in the ink tank.

This function is implemented by reverse-flowing ink to the ink tank by opening and closing the supply 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

- 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

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Mechanical Drive Unit

Ink flow

Ink tank

Ink supply valve

Waste ink from cap for suction and capping

Maintenance cartridge

Carriage unit

Joint

Suction pump

Waste ink from sub cap for capping

Waste glycerin