SHARP LPE151 Technical Report

Date: Apr. 26, 1993

LASER PRINTER : JX-9600 SERIES

No. : LPE-151

TROUBLESHOOTING WHITE STREAK
OCCURRENCE

1.Model name: JX-9600 series laser printer furnished developer cartridge, JX-96NDE, and JX-96DCE.

2.General: When the JX-9600 series developing cartridge is being aging tested continuously, white

streak may possibly appear around 6,000 pages.

3.Phenomenon: When pages are printed at about 6,000 to 8,000 pages in the aging test mode, white
streak appears.

➀ No problem could be recognized in the normal test pattern.
➁ It may be seen when the test pattern of one by one is used.
➂ It may be recognized or not be recognized on the gray scale pattern used by actual

application, depending on the percentage of grays.

➃ The problem may not appears frequently in the print work close to the actual

operating environments.

4.Cause: ➀ We found a developer lump near the MX roller bearing. We also found a lump from oil

leaked through the bearing.

➁ Developer deposit also found at the tip of the DV doctor blade. These causes

resulted in an improper developer brushing, ending in white streak appearance.

SHARP CORPORATION Printer and Scanner Division

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Orange

C

5.Description: 1. Cause and action to be taken

Where changes and additions are made Reason changes and additions are made

➀ Changing the bend in the DV plate
➁ Changing the plane C of the DV doctor
➂ Addition of a DV reinforcing plate

This is done in order to help better flow of the
developer.
To avoid developer deposit on the DV doctor
blade.
Reinforcement is provided after the change in

➀.

➃ Addition of an MX seals, L and R
➄ Changing the shape of the DV side seal
➅ Version label changed from C to D. OP label

changed from white to green.

➆ Addition of a DV bias voltage plate
➇ MG roller surface treatment
➈ Addition of rib to the MX roller

This is to prevent intrusion of a developer lump
to the image area.
This is done for the change in ➁.
These are to distinguish the existing item from
the new item.
By adding the negative developer bias voltage,
deposit of the developer on the DV doctor
plate is prevented.
This is done to allow better flow of the
developer.
This is to improve stirring of the developer.

* NOTE-1: For the whole unit replacement is needed, there is no change involved for

single parts code.

2. How to identify the developer cartridge used for problem elimination The developer

cartridge itself can be identified by the description in (➅). Besides, the original
developer cartridge supplied with the product and the consumable can be easily
recognized by a 25mm large “D” stamped on it.

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