LBP Series Laser Printer Troubleshooting and Maintenance

First, common faults and exclusion

If you find the following lights show, you can remove them one by one by following the steps below.

<Start>->Turn On Power Switch->Power Off

Second, image failure troubleshooting

(I) List of bad images:

(B) the exclusion of image defects:

The occurrence of image defects indicates the inside of the laser printer. The image, development, transfer, and fixing failures can be handled by referring to the following steps.

Treatment of 1-1 light-colored phenomenon

1-2 color depth phenomenon

Treatment of 1-4 Irregular Black Lines

1-6 Treatment of Paper Back Dirty

Third, fault analysis and routine maintenance

(I) Common Causes of Failure

The internal structure of the laser printer is more complex, and the more functions the machine has, the more electrical and mechanical devices are. The use and maintenance will also encounter some unexpected problems. The following are some of the more common causes of failure.

1. Reasons in operation

The machine performance does not understand, improper operation during use, such as the violation of operating requirements, the use of substandard paper, polar toner, causing repeated jams or poor printing results.

2. The impact of the environment

The machine environment does not meet the requirements for a long time. For example, if the temperature is too high and the humidity is too high, especially the latter, it may easily cause the electrode itself to knock down or generate sparks through the photoconductor layer of the photoconductor drum, so that black spots or partial defects appear on the proof sheet.

3. Inconvenient maintenance

The cleaning work is very small, the internal pollution is serious, the number of printing exceeds a certain limit, and does not clean, causing the machine, toner spillage, optical components to be dirty, the paper path components are not working properly, the separation is weak, and the cleaning components are ineffective. Affecting component temperature changes, these integrated faults are sometimes very serious, not only the printing effect is poor, and even the machine can not run.

4. Failure to deal with the problem is not timely, resulting in greater failure

If the paper is not removed when the paper is completely removed, the corner paper jam will prevent the machine from operating. After the breakdown of the electrode, the toner will remain on the photosensitive drum. If it is not processed in time, the wear of the photosensitive drum will increase; when the card is removed, Excessive force, breaking electrode wire, unable to print.

5. Improper maintenance practices

When the machine is repaired, improper maneuvers and stiff movements, such as replacing the gears, no alignment of the card wheel, etc., pushing and pulling forcefully, installing the electrodes, inserting the electrodes in a wrong position, cleaning, and energizing them when not in use, short circuit some parts of the machine. , there is a bigger failure.

6. Human failure

Failure after replacement of consumables or parts; replace with electrode wire that is not the original specification. Too thick or too thin; replacement of electronic components, only pay attention to the shape of the part, without paying attention to its characteristics (voltage and current) to make it damaged or inoperative.

(B) Analysis of the cause of failure from the quality of proofs

The use of proof quality to determine the failure of the various parts of the machine is one of the most frequently used methods. It must be based on understanding the basic principles of the printer's entire working process. Although this method is not directly to find a fault site, but through the flaws on the proofs, rickets may be more accurately find the majority of the fault, so the right medicine, improve work efficiency.

1. Print proof quality requirements

The printer should have a certain image density and contrast, and should at least guarantee reading;

1 The level of printing should be rich, and it should not lose the middle level, that is, grayscale;

The resolution of 2 characters should generally be met to ensure the clarity of the image;

3 proofs of paper without damage, wrinkles, scratches or Other damage to the texture of the paper;

4 The fixing of the printing product is moderate, and the toner image is firmly attached to the surface of the paper, and should not be penetrated to the back, nor should it be slightly melted down, and the paper becomes yellow or hardened;

5 printing products without bottom ash, clean appearance, no other stains;

6 The characters at both ends of the print should have the same depth and depth, without any unevenness.

(3) Causes and Treatments of Defects in Printing Machines

In general, when the number of prints of the printer exceeds a certain number of sheets, the quality of the proofs is slightly insufficient. At a certain time, some visible defects may occur, sometimes the images are completely white or black, and the images are poorly defined. , The image density is not uniform, and the resolution of heating is low. The number of printed ash increases. There are blanks in the printing products, the contrast on the printing products is not enough, etc. The following specific analysis.

1. Phenomenon: There is no image output and the paper is dark.

Cause and disposal

1) The laser is definitely good, and it is possible that the control circuit and scan drive circuit have failed.

2) It is possible that the video card has failed.

3) It is possible that the peripheral circuit of the extended memory has failed.

2. Sample white

1 optical section

1) The laser is damaged and the laser control circuit is damaged.

2) Poor contact.

3) The optical system is blocked by foreign matter (paper, etc.).

4) The scan drive circuit is faulty and there is no scan.

5) The internal temperature sensitization drum, the lens surface condensation water, clean boot heat.

2 charging section

1) The charging electrode is damaged.

2) There is no output from the high voltage generator, a fault occurs or the charging pole connection is broken.

3) Poor contact of the transfer electrode, no image on the drum surface.

3 mechanical parts

1) The pinion detection tip (stainless steel) of the transmission gear cuts off the bite portion of the internal gear so that the shaft rotates and the gear does not rotate, so that the photosensitive drum does not output all the white paper.

2) The tip of the main drive gear is disengaged, resulting in the separation of the gear and the shaft. The shaft rotates and the gear does not turn, resulting in full whiteness.

3. The printing product image is dirty

Phenomenon, the printed product is not clean, the image part is stained, can be divided into two cases of rules and no rules.

The regular image dyeing often appears in a certain part of the printing product, which corresponds to the contamination and damage of the parts of the machine.

1 Drum surface contamination, oil stains, fingerprints, or scratches on the surface of the drum, cleaning or replacement.

(2) In the developing section, the toner is stained with a solidified toner block on the developing roller, so that the capability of adsorbing powder at the place is strengthened and removed.

Example: A screw is stuck on the photosensitive drum, resulting in poor rotation. There is a vertical line to eliminate it.

3 cleaning section

1) The photosensitive drum cleaning device is damaged. If the cleaning blade has a gap or the other side is low, replace it.

2) Transfer electrode, left and right non-uniform, or charging and left and right non-uniform, leading to left deep right, or left deep right shallow band pollution, cleaning or replacement.

4 fixing section

1) Deterioration of rubber on the surface of the heating roller due to aging, scratches, or cleaning brush of the fixing roller, resulting in local contamination of the heating roller and replacement.

2) The upper heating roller of the fuser is scratched and replaced.

3) The fuser thermal switch (disconnects the power supply when the temperature is reached) and the thermistor sensor (feeds the CPU with a temperature value), when the paper and the working environment are not clean, the surface is likely to attract dust, agglomerate, increase the thickness, The gap is reduced, resulting in increased friction, damage to the heating roller and the thermistor sensor, and replacement.

Example: It takes nearly two hours to heat. It may be thermistor failure or agglomeration on the surface of the thermistor. The heat insulation layer will cause the temperature to not pass in. After replacing the fuser unit, it is normal.

With respect to dust, the climate in the north and southwest of China is dry, so there are more dust, and in some places, the offices are even worse. Dust should be reduced as much as possible.

Solution: In case of scratches, replace the thermistor and the upper heating roller.

5 paper supply section

The pickup roller is contaminated with toner, leaving a trail of the pickup roller at the front of the paper, which may appear in different parts of the print during the printing process.

4 printing products have stripes

1 Development section

1) The agitator device in the developer is malfunctioning, the toner accumulates at one end, leaks out, spills on the paper, and is repaired or replaced.

2) After the toner gets wet, it falls on the photosensitive drum or the surface of the paper, causing spot-like contamination and powder exchange.

3) The carrier is stained with carrier and toner around the developer and is absorbed by the photoreceptor drum, or the wine directly falls on the paper and appears smudged and cleaned.

Fourth, general maintenance and repair

Regular cleaning and maintenance are necessary to extend the life of the printer and keep it in good working condition.

1. Maintenance of the printer

● Do not place anything on top of the printer. Do not stack excess paper on the tray that faces upwards.

● Never open the front cover during printing.

● After the printer is turned off, wait for a few minutes to cool and cover the dust cover.

● If you do not use the printer for a long period of time, it is best to unplug the power cord from the outlet and take out the toner cartridge and put it in the original bag.

● Do not disassemble the printer.

Daily cleaning

Use a clean damp cloth or special