Continuation of part 1

This time we shall consider toner cartridge defects, their aftermath and ways to fix them. Previously we found that cartridge consists of several part. Despite the small amount of parts, there are enough factors affecting quality of printing.

1. Organic Photo Conductor (OPC)

OPC is also known as photo drum, drum, photoreceptor or photoconductor. On its surface a toner image to be transferred to paper is created. This dictates peculiarities of its functioning.

Problem with photo drum of cartridge for Hewlett-Packard LaserJet 1200 printer.

Most common defect is black patterns appearing on the print’s edges. This means the photoreceptor is critically worn out. Photo sensitive coating is rubbed off, and toner first adheres to “naked” drum and then gets transferred to paper.

This is how the worn-out looks like on the photoreceptor. Factually, this is a physical process of drum coating rubbing against paper and toner.

Unfortunately, the problem can only be solved by replacing the drum. All known efforts to restore photosensitive coating show little or no results, when it comes to equipment testing. However, in a year or so the technology advances and a photoreceptor can be restored even at home.

Faulty parts are not always the reason of bad prints or photocopies. Dirt, dust and toner coarse grinding may also cause black marks on freshly churned pages.

The dirt between the wiper blade and the photo drum clearly exhibits itself:

And it finds its way to the prints:

This issue gets fixed simply by reassembling the cartridge. Most easy and faster way is to complete replace the cartridge.

2. Primary Charge Roller (PCR)

The second component of the printing system is PCR. This is a spongy roller that applies initial charge and removed residual charge from the drum. The roller is actually a metal rod in a rubber coat. Troubles it can “reward” the prints will always be noticable.

You can never tell working PCR from faulty just by looking at them:

But prints made with new and old PCR tell you everything:

Charge rollers cannot be repaired, only replaced with a new.

Joins us next time to learn other cartridge defects and ways to fix them.

Popularity: 2%

Submit to:

If you enjoyed this post, make sure you subscribe to our RSS feed!

This article covers common issues that rise during the use of most toner cartridges. For practical purposes the cartridge examined is made by Hewlett-Packard and there are reasons for that. First, this brand has long been a leader on printer market. Second, cartridge refilling which is still widely used by small business and home offices.

What you see above is a perfect test page. Of course, it’s a 99% merit of new original cartridge. Original makers of printer consumables have a smoothly running production and high-level quality management. Up to 2% of total output is tiny figure for rejection rate provided by major brands. However, that doesn’t mean third-party manufacturers make cheap and inferior products. Compatible printer cartridges can also be reliable in use. It’s all a matter of specific brand, it’s quality management and, surely, the warranty.

Considering that cartridges get refilled, it come as no surprise that after 5-7 refills printing artifacts appear. This is caused by time, lifespan, yield and low quality of parts, and sometimes carelessness of laborer or production equipment failure.

Practically speaking, here is a good example for this article:

The look of this page can tell you that the cartridge is empty, charged roller is broken, there’s a split between developer roller and toner hopper and photoreceptor drum requires replacement. Reading these problems from a printout is easily available to everyone, regardless of his job position or level of technical skills. Don’t you agree it’s great to know a bit more than others and to put that knowledge to use?

What a cartridge is made of?

These are the cartridge parts involved in the process of printing

The picture above shows parts of HP Q2612A toner cartridge, but they are common for most HP monochrome cartridges. From top to bottom:

• Wiper blade (cleans excessive toner from the drum)
• Photo imaging drum (creates initial image)
• Charged roller (charges and discharges the drum)

Magnetic roller and metering blade responsible for toner transfer to photo drum are missing from this picture. All together these parts make up imaging unit. Some cartridge makers, unlike HP, separate drum from toner unit.

In the next part we wil turn from theory to practice.

Popularity: 2%

Submit to:

If you enjoyed this post, make sure you subscribe to our RSS feed!