10.B - Maintain Inkjet printers Flashcards
Describe an Inkjet printer.
An Inkjet printer forms images by firing microscopic droplets of liquid ink out of nozzles mounted together on a carriage assembly that moves back and forth across the paper. The printer can use heat or vibrations to release the ink.
What colors do Inkjet printers use?
CMYK (Cyan, Magenta, Yellow, and Black [K])
Light magenta and light cyan used in higher end printers
Describe the Inkjet printing process
An inkjet print head is composed of a series of very small holes or nozzles, the ink reservoir is kept at a pressure slightly below that of the ambient pressure to keep the ink from coming out of the holes.
Small controlled amount of ink is forced through voltage-charged deflection plates and onto the paper.
A stepper motor moves the print head across the page, advancing a tiny amount each time.
Synchronizing this action with the movement of the print head across the paper, text and images can be built up in a series of differently shaded or colored dots.
Ink can be applied in one direction only (unidirectional); on others, ink is applied on both the “outward” and “return” passes over the page (bidirectional).
A cleaning cycle to the print head to remove any dried or clogged ink is applied if the printer has been sitting idle for some time
Why are Inkjet described as line printers?
Inkjet printers are line printers—where laser printers are page printers—because they build up the image line-by-line
What are two main Ink Delivery Systems (IDS)?
The charge (or piezoelectric) method is used by Epson.
The thermal method is used by HP, Canon (who refer to it as Bubblejet), and Lexmark.
Describe Thermal print heads.
The ink at the nozzle is heated, creating a bubble. When the bubble bursts, it sprays ink through the nozzle and draws more ink from the reservoir.
What are the pros/cons of thermal print heads?
They are cheaper and simpler to produce,
But the heating elements have a relatively short life.
Most thermal printers use a combined print head and ink reservoir. When the ink runs out, the print head is also replaced.
Describe Piezoelectric print heads.
The nozzle contains a piezoelectric element, which changes shape when a voltage is applied. This acts like a small pump, pushing ink through the nozzle and drawing ink from the reservoir.
Epson piezoelectric print heads are non-removable and designed to last as long as the rest of the printer components.
Name two Inkjet maintenance operations
Print head cleaning - Use the printer’s cleaning cycle found in the maintenance menu
Print head alignment— This is typically done automatically when you replace the ink cartridges.
