Konica Minolta Bizhub C7000 - Part keeps rotating, while it shouldn't

[Honpress]

Hi there!

Yesterday I suddenly heard a strange noise in the machine behind the transfer belt unit. Pulled out the process unit and saw this white part was still rotating while nothing was being printed. I've attached a picture of it. It's the white round part in this photo. Also have a video of it, don't know how to attach it though...
Don't know what the part is called, can't really find it in the manual. Could only find something about the transfer pressure release motor M19 or M34.

keeps spinning.jpg

I'm almost certain it's not suppose to continuously rotating, only when the toner from the drums needs to be applied on the transfer belt.
It creates a huge mess with toner spread everywhere, because the pressure of the rolls underneath the transfer belt are not properly working.
I have registration problems, can't fix it and followed the steps in the service manual. But pretty sure this rotating part is messing everything up.

When I make a print, the beginning of the print on the paper is fine, but the colors shift on the rest of the paper.

What makes this part keep rotating while it shouldn't? How can I make it stop and let it rotate en stop on the right time like it should, so it doesn't break the pressure part in the transfer belt unit. Everyday something weird with this printer haha. Hope somebody can help me out, Thanks!

Ilse

[blackcat4866]

As dirty as it appears in there, I suspect you've got a dirty photosensor, either the patch sensors, or the sensor that detects movement of the primary transfer shift. Sorry, I can't seem to locate the specific sensor numbers. Be careful not to vacuum directly over sensors, the static electricity generated by vacuuming up developer can damage them.Use a blower brush or toothbrush or both to clean photointerrupters. My favorite tool for that is interdental brushes:
https://www.amazon.com/Interdental-C...5c031f9f55d5&h vocijid=11914231491105846967-B097TM9QGF-&hvexpln=73&hvadid=692875362841&hvpos=&hvnetw=g &hv rand=11914231491105846967&hvpone=&hvptwo=&hvqmt=&h vdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9017042&hvtarg id=pla-2281435183858&psc=1

Interdental Brushes.jpg

Clean all sensors in the immediate viscinity and inside the intermediate transfer belt unit.

[Synthohol]

the toner filters box can be dirty so all the misted toner collects instead of being sucked up.
maybe ps15 is dirty or the keyhole is dirty?
ps15.jpg

[Honpress]

As dirty as it appears in there, I suspect you've got a dirty photosensor, either the patch sensors, or the sensor that detects movement of the primary transfer shift. Sorry, I can't seem to locate the specific sensor numbers. Be careful not to vacuum directly over sensors, the static electricity generated by vacuuming up developer can damage them.Use a blower brush or toothbrush or both to clean photointerrupters. My favorite tool for that is interdental brushes:
https://www.amazon.com/Interdental-C...5c031f9f55d5&h vocijid=11914231491105846967-B097TM9QGF-&hvexpln=73&hvadid=692875362841&hvpos=&hvnetw=g &hv rand=11914231491105846967&hvpone=&hvptwo=&hvqmt=&h vdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9017042&hvtarg id=pla-2281435183858&psc=1

Interdental Brushes.jpg

Clean all sensors in the immediate viscinity and inside the intermediate transfer belt unit.

Hi Blackcat,

Thanks again for your response!
I cleaned the sensor in the back (it was a bit dirty) that is reading the white rotating (driver?) Is that the photosensor?
What are the patch sensor and movement detect sensor?

Which sensors are in the intermediate transfer belt unit.? Sorry for the questions But I had cleaned everything in this as well.

[Honpress]

the toner filters box can be dirty so all the misted toner collects instead of being sucked up.
maybe ps15 is dirty or the keyhole is dirty?
ps15.jpg

Hi Synthohol, thanks for your response again!
Is ps15 the Photosensor? I cleaned that one, it was a bit dirty.
But still have the same problem that the colors keep shifting most of the time. Little time it doesn't that. What else can I do?

[blackcat4866]

I was thinking of PS15, like in Synthohol's photo.

Are you getting C4651, C4661? I struggles with a machine at setup. The drive coupler was not engaging completely with the transfer belt drive.

[davel]

So, when you open the machine to pull parts out it doesn’t cut power to the drives?

[Honpress]

I was thinking of PS15, like in Synthohol's photo.

Are you getting C4651, C4661? I struggles with a machine at setup. The drive coupler was not engaging completely with the transfer belt drive.

No I'm not getting any error code.. Maybe that would have been better so know where to look.
When this problem first occurred I started the Color registration manual. It was way off, so I started adjusting like i the manual. And every time the print was different. When I thought I had it right, it came out totally wrong. So I figured it probably should be something else.
I have to mention we have moved with our company and moved the printer our self. We have done this before like 2 times already (because well we got screwed over a lot and have had a lot of bad luck short story) I first thought maybe something could have got out of his position.

Now I have the shifting problem mostly on the inlay of the paper. Could it be that the paper isn't transferred properly at the transfer belt? Or does it has something to do with the Belt Line Speed, because this is (on the top of my mind) 302.1 and the drums speed are 301.2 something. Shouldn't they have the same speed.?

[Honpress]

So, when you open the machine to pull parts out it doesn’t cut power to the drives?

Hi Davel, thank you for your response! What exactly do you mean? Sorry English isn't my mother tongue, so sometimes not sure if I (or the internet) translate it right.
You mean the white part that kept turning even if I pulled out the transfer intermediate unit?

[davel]

Normally when you open a machine the door switches cut power to the drive of the machine so that user’s cannot get caught in moving parts.

[Honpress]

papier A4.jpg

Normally when you open a machine the door switches cut power to the drive of the machine so that user’s cannot get caught in moving parts.

Well at first that white part kept rotating, so far it hasn't done that anymore..
I just made a print format A4. As you can see the beginning of the paper (inlay) the print shifted. If I print a few of these, sometimes it's less or the same. I've added a photo of it

[blackcat4866]

It is difficult to see the primary transfer belt drive operating, because it is covered with the imaging unit closed. To get an image like you have posted, there is definitely a drive issue somewhere between the motor and the belt. It could be a damaged drive pin, a damaged gear, a damaged roller bearing, or uneven tension on one of the transfer belt rollers. You will need to start turning the drive components by hand, to see that the gear teeth engage and are in good condition, to see that the gears that are pinned to the shaft do not turn freely, to see that the tension is even across the rollers in the primary transfer belt unit. Maybe a translation will help:

Het is moeilijk om te zien hoe de aandrijving van de primaire transferriem werkt, omdat deze is afgedekt met de beeldvormingseenheid gesloten. Om een afbeelding te krijgen zoals je hebt gepost, is er zeker een aandrijfprobleem ergens tussen de motor en de riem. Het kan een beschadigde aandrijfpen zijn, een beschadigd tandwiel, een beschadigd rollager of een ongelijkmatige spanning op een van de transferriemrollen. Je moet de aandrijfcomponenten met de hand ronddraaien om te zien of de tandwieltanden goed vastzitten en in goede staat zijn, om te zien of de tandwielen die aan de as vastzitten niet vrij ronddraaien, om te zien of de spanning gelijkmatig is over de rollen in de primaire transferriemeenheid.
=^..^=

[Honpress]

It is difficult to see the primary transfer belt drive operating, because it is covered with the imaging unit closed. To get an image like you have posted, there is definitely a drive issue somewhere between the motor and the belt. It could be a damaged drive pin, a damaged gear, a damaged roller bearing, or uneven tension on one of the transfer belt rollers. You will need to start turning the drive components by hand, to see that the gear teeth engage and are in good condition, to see that the gears that are pinned to the shaft do not turn freely, to see that the tension is even across the rollers in the primary transfer belt unit. Maybe a translation will help:

Het is moeilijk om te zien hoe de aandrijving van de primaire transferriem werkt, omdat deze is afgedekt met de beeldvormingseenheid gesloten. Om een afbeelding te krijgen zoals je hebt gepost, is er zeker een aandrijfprobleem ergens tussen de motor en de riem. Het kan een beschadigde aandrijfpen zijn, een beschadigd tandwiel, een beschadigd rollager of een ongelijkmatige spanning op een van de transferriemrollen. Je moet de aandrijfcomponenten met de hand ronddraaien om te zien of de tandwieltanden goed vastzitten en in goede staat zijn, om te zien of de tandwielen die aan de as vastzitten niet vrij ronddraaien, om te zien of de spanning gelijkmatig is over de rollen in de primaire transferriemeenheid.
=^..^=

Haha Thnx I love it! You're the best!

Yeah also thinking about that, so going to check everything and clean the whole thing, because there was toner everywhere before, even inside the transfer belt unit on the rollers etc.
That doesn't do any good either I suppose and mess everything else up. Hopefully I can find the problem and fix it.
Frustrating because I was really happy I once got the printer almost perfectly working all done by myself.
It's an old printer so of course things need to be replaced. The last years haven't been easy for us on the job, so that's why we try to replace/repair much as possible ourself. Otherwise a service engineer would be really nice. But I'm learning thanks to you guys on this forum and the internet.

[Honpress]

So I cleaned the transfer belt unit. When I manually turn the transfer belt (without the transfer belt cleaning unit attached), I don't notice anything weird and rotates normally.
But is it normal that the white gear on the top side doesn't move for a moment when I start to rotate? I can make a video if that helps, to see what I mean.

If I attache the transfer belt cleaning unit and turn the belt (I hope I'm doing it the right way, clockwise if you standing in front of the machine) the belt itself won't rotate. The gears do rotate.
What else can I do? I printed the same prints as above and came out the same.

[blackcat4866]

When you insert the primary transfer belt unit, the first time you power up it must make one rotation for the coupler to engage, so the belt will be still for a single rotation of the drive coupler, then from then on rotate with the drive. Can I see the video?