Laser printing is a digital printing process that rapidly produces high quality text and graphics on plain paper. As with digital photocopiers and multifunction printers (MFPs), laser printers employ a xerographic printing process, but differ from analog photocopiers in that the image is produced by the direct scanning of a laser beam across the printer's photo-receptor.
Photoreceptor
Most consumer and small business laser printers use a toner cartridge that combines the photo-receptor (sometimes called "photo conductor unit" or "imaging drum") with the toner supply bin, the waste toner hopper, and various wiper blades. When the toner supply is consumed, replacing the toner cartridge automatically replaces the imaging drum, waste toner hopper, and wiper blades.
Wiper blades can fail even in new, unused toners that have been stored for a few years; a failed wiper blade will manifest itself as ghosting and/or full page shading.
Print Page Tracking
Some laser printers maintain a page count of the number of pages printed since last maintenance. On these models, a reminder message will appear informing the user it is nearing time to replace standard maintenance parts. On other models, no page count is kept or no reminder is displayed, so the user must keep track of pages printed manually or watch for warning signs like paper feed problems and print defects.
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| Laser printer parts and components. |
Calibration Cycles
Some color laser printers, notably some Lexmark models run "calibration" cycles even when no printing has occurred for weeks. This can waste a significant amount of toner from each reservoir, in addition to consuming electricity. This has a significant impact on printing economy, especially in low-volume applications. On some models these calibration cycles can be disabled via a menu choice, for others the printer must be unplugged to avoid this waste. Printers that have this issue have a replaceable "waste toner bin", which is another periodic operating expense.
Life Expectancy Charts
Manufacturers usually provide life expectancy charts for common printer parts and consumables. Manufacturers rate life expectancy for their printer parts in terms of "expected page-production life" rather than in units of time.
Business Class Versus Personal Laser Printers
Consumables and maintenance parts for business-class printers will generally be rated for a higher page-production expectancy than parts for personal printers. In particular, toner cartridges and fusers usually have a higher page production expectancy in business-class printers than personal-class printers. Color laser printers can require more maintenance and parts replacement than monochrome laser printers since they contain more imaging components.
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| Roller assembly. |
Rollers and Assemblies
For rollers and assemblies involved in the paper pickup path and paper feed path, typical maintenance is to vacuum toner and dust from the mechanisms, and replace, clean, or restore the rubber paper-handling rollers. Most pickup, feed, and separation rollers have a rubber coating which eventually suffers wear and becomes covered with slippery paper dust. In cases where replacement rollers are discontinued or unavailable, rubber rollers can be cleaned safely with a damp lint-free rag. Commercial chemical solutions are also available which may help temporarily restore the traction of the rubber.
Fusing Assembly, aka Fuser
The fusing assembly (also called a "fuser") is generally considered a replaceable consumable part on laser printers. The fusing assembly is responsible for melting and bonding the toner to the paper. There are many possible defects for fusing assemblies: defects include worn plastic drive gears, electronic failure of heating components, torn fixing film sleeves, worn pressure rollers, toner buildup on heating rollers and pressure rollers, worn or scratched pressure rollers, and damaged paper sensors.
Laser Printer Preventive Maintenance Kits
Some manufacturers and third-party parts suppliers offer preventative maintenance kits specific to each printer model; such kits generally include a fuser and may also include pickup rollers, feed rollers, transfer rollers, charge rollers, and separation pads. These same sources may offer a trade-in credit for the return of failed fuser assemblies, which they later rebuild for resale.
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