Operating Principles

2.4 Ink System Management

This section explains how the ink system is controlled to protect the printheads and to ensure high print quality. The ink system consists of following operations:

￿Power On

￿Initialization

￿Ink Cartridge Replacement

￿Cleaning

￿Print Start

￿Flushing

￿Waiting

￿False Absorption

￿Wiping

￿Rubbing

￿Micro Absorption

￿Carriage Lock

The printer also selects an ink sequence based on the printer condition by referring to the value for the timer counter IC that has a back-up lithium battery and timer counter stored in the ￿￿￿￿￿!. The printer has following counters:

￿Protect Counter A

￿Ink Consumption Counter

￿One-time Flag

2.4.1 Ink System Operations

The ink system operations are as described below.

￿Power on

Performed when the printer is turned on. It performs a cleaning sequence by referring to the counter value.

￿Initialization

Performed when the printer receives the initialization command. The ￿￿ returns to the home position and holds during this operation.

￿Ink Cartridge Replacement

Performed through the control panel operation when the ink cartridge needs replacing. It determines whether the ink cartridge is installed or not and performs a cleaning sequence if necessary.

￿Cleaning

Performed to solve decline in print quality caused by the abnormal nozzle status such as nozzle clogging and inaccurate ink ejection.

￿Print Start

Performs the cleaning or flushing operation before the printer starts printing after power on.

￿Flushing

Performed to eject few ink dots during printing to prevent increase in ink viscosity.

￿Waiting

Performs the flushing operation after the printing operation to avoid nozzle clogging caused by the viscous ink.

￿False Absorption

Absorbs the ink inside the cap and eliminates the ink on the nozzle plate after ink is absorbed.

￿Rubbing

Performed to eliminate the ink and dust that adheres on the nozzle surface. Few dots of ink is absorbed to moisten the nozzle surface prior to this operation.

￿Micro Absorption

Performed to eject bubbles formed inside the cavity.

￿Carriage Lock

Locks the carriage when turning off the printer or no printing is performed for 5 minutes or more with the printer power on.

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