iRC5185 sub scan registration shift continues

[Toner Boy]

Back again after 2.5 months, approximate 1mm shift between each color (or less). History: new ITB belt, FU7-0406-000 drive gear (on ITB), swing gear assembly, cleaning blade unit. Had to run Quick and Full Gradation adjustments after these parts were installed to regain proper registration. Cleaned ITB rollers, cleaned pattern reader/salt sensors.
We can regain proper image by running Quick Gradation adjust and/or Full adjust but now is only lasting a couple days at best. METER: approximately 900K.
Considering FM2-5361-000 ITB drive assembly but don't think this meter is high enough, and don't believe laser units affect sub-scan at all (correct me if I'm wrong?).
Have not performed DC Con clear yet, could corrupted data be intermittent as such?

[Canuck]

Re: iRC5185 sub scan registration shift continues

Gradations will not correct image registration issue..read the book. Just a coincidence. Check that patch reader is seated properly. Have you replaced the internal drive rolls on itb assembly? Also if the external secondary transfer roller is stiff to turn it will cause color misregistration.

[Toner Boy]

Re: iRC5185 sub scan registration shift continues

Secondary roll is smooth to turn, have not replaced internal rolls in ITB but were cleaned and inspected recently. Patch reader appears to be installed correctly, was taken out and thoroughly cleaned for this issue a couple months back.

[teckat]

Re: iRC5185 sub scan registration shift continues

Secondary roll is smooth to turn, have not replaced internal rolls in ITB but were cleaned and inspected recently. Patch reader appears to be installed correctly, was taken out and thoroughly cleaned for this issue a couple months back.

--------------------------------------
Make sure Rear rail is not loose or that it has not been moved.

u probably need to do a Front Side ITB Rail adjustment / have also seen a cracked rail

it's in manual> there is a procedure > but I just try and eyeball it>

remove cover to view ITB Rotation> run 20/30 PG 6 GRID TEST PAGES< look in to see if ITB Belt is shifting

see attachment for Canon procedure disregard belt tear & serial # info in pdf

[boog]

Re: iRC5185 sub scan registration shift continues

I have seen similar issues from the ITB being installed backward. Causing the tabs on the edge to catch on the cleaning unit.

[hotsun]

Re: iRC5185 sub scan registration shift continues

Go into the maintenance mode, enforce the color in the right position.

[teckat]

Re: iRC5185 sub scan registration shift continues

iRC5180_Color_Shift_Prevention _&amp;_Correction.pdf

The Color Registration in Printer Mode (PG-Type6) is dependent on the 4 Lasers, the Test Pattern Reader, the IMG Board and the Maisy Board (DC Controller) as well as on ITB Drive status.
In any case, an Image Processing Board, Motherboard or Sub Board could never be the cause.

Method for correcting/ preventing Lasers from printing out of registration.

1. Remember:
The four Laser Units that equip the iRC4580i series are identical. Therefore they can be interchanged to identify a
breakdown. Nevertheless, there are a few things to remember.

2. Principles:
a: Horizontal registrationb: Vertical registration
The four Laser Units are vertically registered according to the ITB Test Pattern. Again, the yellow Laser serves as reference for the other colors.

c: Aligning the horizontal lines of the Laser
Since the four Lasers are independent and since they sit side by side on the Machine Frame, it is possible that even when registration is set, the lines might still not print out parallel. In order to correct this, each Laser has a Lens Motor.

This (Step) Motor enables perfect alignment of each color. The latter setting is assured through reading the Test Patterns on the ITB. The black Laser serves as reference for this registration.
Indeed, the Black Laser Unit Motor is inactive and its Lens is set in the middle position by default. The Y,M,C Laser Lens Motor correct the output position for each Laser output by aligning themselves with the unchanging black position.
It is therefore important to remember, when exchanging the Black Laser with that of another color in the machine, that the Laser Unit that serves as black must always have the Lens Motor in the middle position.
This is never the case if it has been swapped with a unit that has served as a Color Laser, as the Lens correction position system has been activated to print.

see pdf for further test adjustments

[Toner Boy]

Re: iRC5185 sub scan registration shift continues

Was there Friday. They have two identical machines, initially I thought the pattern reader cover was not opening all the way causing the PG6 printout error, as when forced open all the way it seemed to fix the issue (until I ran some pages one last time before leaving). Registration is not always off to the same degree, sometimes 1.5mm, sometimes .5mm, machine does not have to perform any calibrations to vary. checked ITB rails for cracks or looseness (they are solid). Detailed inspection of ITB for slipping or bad gears, all looks solid. Each color is offset by the same distance.
Swapped ITB belts between machines and both were working fine when I left. Makes no sense, but will see if problem travels to second machine.See prints here: PG6.pdf

[Toner Boy]

Re: iRC5185 sub scan registration shift continues

To me it seems like the ITB motor is inconsistent in speed during the registration pattern reading, but I've been second guessing this a lot. From what I can tell there is a slight variance in image width (lead to trail edge) as the page travels through the machine so I'm leaning towards the motor dragging down for one reason or another. Maybe the motor is stronger in the second machine so when the ITB units were swapped no effect was noticed. Thanks to all for your input so far. I also did a REG-CLEAR in svc mode 2 with no results.

[elamurugu]

Re: iRC5185 sub scan registration shift continues

Go to service mode and take test page ymck after you cheak witch colour pattern indencity is not good replace that drum ass. if any colour indencity is not proper the pattern reading sensor output is registration shift.

[teckat]

Re: iRC5185 sub scan registration shift continues

Correcting Image Displacement/To correct the discrepancies in images, the machine executes corrective control for image position; it detects displacement in color by forming a pattern of a specific color on the transfer belt and reading it against the correct position.

from DC controller PCB 1--The machine uses the acceleration/deceleration signal to control the speed of rotation of the laser scanner motor so that the BD signal from individual laser units will be of the same phase as the reference signal (if the BD signal is behind the reference signal, accelerate; if ahead, decelerates).


have u pulled out all the LASERS to do a Manual set > to all Lens Motors Cams to there middle positions


SUB SCAN =paper feed direction=The Y pattern is used as the reference.
The synchronization in sub scanning direction is controlled with reference to the PTOP signal (image formation start signal).
- When the mechanism becomes ready for image formation, the PTOP signal (image formation start signal) is generated, turning on the individual lasers based on the signal.
SUB SCAN.JPG

MAIN SCAN=cross feed (front to back)= The Bk pattern is used as the reference
The control of synchronization in main scanning direction is based on the BD signal.

MAIN SCAN.JPG

[Toner Boy]

Re: iRC5185 sub scan registration shift continues

UPDATE: Replaced the ITB belt drive unit (that was fun...), swapped ITB belt assemblies back to their original locations, performed REG-CLR and full gradation, cleaned bushings for secondary transfer roller, looks good for now but not holding my breath...
NOTE: problem seemed to travel with the ITB belt unit to the other machine but without such severe offset as when in the original machine. Both ITB belts rotate just as easily out of the machine, maybe when ITB rollers are engaged there is more drag. If problem returns will recheck belt unit components. No main scan offsetting has ever occurred on this unit. And thanks again for your help on this.

[boog]

Re: iRC5185 sub scan registration shift continues

UPDATE: Replaced the ITB belt drive unit (that was fun...), swapped ITB belt assemblies back to their original locations, performed REG-CLR and full gradation, cleaned bushings for secondary transfer roller, looks good for now but not holding my breath...
NOTE: problem seemed to travel with the ITB belt unit to the other machine but without such severe offset as when in the original machine. Both ITB belts rotate just as easily out of the machine, maybe when ITB rollers are engaged there is more drag. If problem returns will recheck belt unit components. No main scan offsetting has ever occurred on this unit. And thanks again for your help on this.

That drive unit is fun, buried in there!

Since the problem is following the ITB unit, I would double check that the belt is the right direction (those seams can catch on the cleaning unit) and clean all the rubber rollers (I use belt restore). Make sure the 2nd inside transfer roller (FB6-2934-000) is fine (no cracks and clean) including shafts and bearings (check to see if the bearing are wearing a groove in the shaft). And the same with the drive roller (FC7-2747-000).

Also check the drive gear for any abnormalities FU3-0267-000

Those are all of my normal suspects that cause issues. I'll also clean the inside of the belt with belt restore, then clean off the belt restore with alcohol.

If the belt is still slipping after that, It might just need a new belt. (FC7-0091-000)

[Toner Boy]

Re: iRC5185 sub scan registration shift continues

We are calling this one 'fixed', installed a replacement ITB belt assembly (along with another pattern reader unit) and let it spin for a couple weeks, when we checked out the old unit the roller that mates with the secondary transfer was resistant to turning, like the black bushings had shrunk on the shaft. Probably much more resistant once pressure applied to it creating belt drag. Some cracks in the rubber were noticed as well, see image.Transfer belt roller.jpg

[boog]

Re: iRC5185 sub scan registration shift continues

We are calling this one 'fixed', installed a replacement ITB belt assembly (along with another pattern reader unit) and let it spin for a couple weeks, when we checked out the old unit the roller that mates with the secondary transfer was resistant to turning, like the black bushings had shrunk on the shaft. Probably much more resistant once pressure applied to it creating belt drag. Some cracks in the rubber were noticed as well, see image.

Those rollers are notorious for cracking. I haven't figured out why they do, must be lots of pressure/pulling on them. But, I have replaced a bunch of them. I think the bushings get toner and dirt on them causing them to slow. Glad you got it running!