Kyocera General Question

[BillyCarpenter]

It's been many years since I've been to a Kyocera school on a color MFP. And I think at the time Kyocera wasn't making a color MFP, they were rebranded Minolta. This was right after Kyocera took over from Mita.

Anyway, I (barely) remember that when the Kyocera color MFP would run calibration that 3 color (C,M,Y) patches would be applied to the transfer belt and would be read by the patch sensor. I think Kyocera is calling it "ID sensor" now. Basically light from the ID sensors would be reflected back to the sensor and the machine would adjust accordingly for the best quality. It's been a while. Do I have that right?

Here's my question: Are there any readings (via Maintenance Report) that you guys pay attention to that would help you diagnose a print quality issue?

[tsbservice]

[BillyCarpenter]

Re: Kyocera General Question

PS - At the moment I don't have a machine that's giving me quality issues. I'm about to do some tests on a Kyocea 3551 to see how certain readings change.

For instance, I'm gonna put in a known damaged transfer belt and see how the readings change under "Stress". I was told it must be above 2600. Anything below that indicates a faulty transfer belt.

There are other tests I'm gonna run to verify information I was given.

Just want to make sure I'm understanding how this machines gathers those numbers.

[BillyCarpenter]

Re: Kyocera General Question

Billy I don't know the answer of your question but here is what I grasped.
It's a bit more complicated. IDC( image density control) sensors are core elements in complicated system. Here is example of what they do in one KM machine. All these controls are parrts of Image Stabilization process.

Description of control

- IDC sensor adjustment control
• Controls changes in characteristics due to change with time and contamination of the transfer belt and IDC sensor, part-to-part variations in
the sensors, and change of environment.
• The intensity (current value) of the IDC sensor is adjusted on the surface of the transfer belt, on which no toner sticks (background level).

- Max. density adjustment control
• The developing bias (Vdc) is adjusted to control changes in the solid density resulting from variations in developing characteristics and IDC
sensor intensity, variations in sensitivity of the photo conductor, and changes in the environment, durability, and the amount of charge in
toner.
• Patterns are produced on the surface of the transfer belt and the IDC sensor detects the amount of toner sticking to them.
• Referring to the detected data and the environment data taken by the temperature/ humidity sensors, the developing bias value that results
in the appropriate maximum density is calculated and stored in memory.
• Thereafter, the grid voltage (Vg) value, including the background margin adjustment value, is calculated and stored in memory.

- LD (laser diode) intensity adjustment control
• It adjusts the variation in reproducibility of the thin line and the reverse outline, which is resulting from the variations in electrostatic
characteristics of the photo conductor, developing characteristics and transfer characteristics in terms of individual difference, environment
and durability, to make it the target level.
• It produces detection patterns on the surface of the transfer belt with the given level of LD intensity and detects the output value of IDC
sensor.
• LD intensity is calculated from the detected IDC sensor data.

- Color registration control (color shift correction)
• In a tandem engine, each four different color has an independent image reproduction process. Color shift may occur because of variations
in part accuracy. The color registration control system automatically detects color shift and correct color shift in the main and sub scanning
directions.
• The color shift is detected as follows. A pattern is produced at each of front and rear ends of the transfer belt. The IDC sensors at the front
and rear ends read respective patterns to thereby calculate and store color shift amounts in the sub-scanning and main scanning directions.
• From data readings, the machine calculates how much the position of each of the different colors should be corrected. Based on the
calculated data, the machine controls each dot during image output, thereby correcting the color shift amount.

- Gamma correction control
• The intensity of LD in all gradation levels is adjusted to correct changes in gradation characteristics to a linear one. The changes in
gradation characteristics are caused by variations in the photo conductor sensitivity and developing characteristics and changes with time
and in environment.
• It produces gradation patterns on the transfer belt and calculates gradation characteristics output by the current engine with the IDC sensor.
• The gamma correction data is calculated using the density measurements of different gradation levels. The optimum LD intensity is set for each of the different gradation levels.

That's very detailed information and it helped to jog my memory. I think that's similar to what Kyocera does.

[blackcat4866]

Re: Kyocera General Question

I'll be interested in any answers that you get.

On the machines that I know the best: Konica Minoltas, Toshibas, and Kyoceras ...

I guess Toshibas are the easiest to understand the process. If the patches are not in a useable range you'll get CE40, CE20, or CA00, depending on whether it's a fault with the color registration patches or the color density patches. Rarely do we have problems with the patch sensors themselves. Sometimes the shutter doesn't open or the sensor gets dirty, but I don't think I've ever had to replace a patch sensor on a Toshiba. Usually the patch is imperfectly formed for a variety of reasons. In this order of likelyhood:

Poor developing/depleted developer
Dirty grid/scorotron
Dirty laser slit glass
Worn drum/poor drum cleaning
Poor primary transfer belt cleaning
Poorly tracking transfer belt
Laser issue in forming the patch

And all of these can be diagnosed by removing the primary transfer belt and examining the patches on the belt immediately after the code occurs. There are 08 modes that record the number of errors for each color and each sensor. I could memorize all those 08 modes or look them up each time ... or I could just pull out the primary transfer belt unit and see (in this order of likelihood):

Voids in the feed direction through a CMY or K patch
Light areas in the feed direction through a CMY or K patch
Lines of CMYK or composite black in the feed direction through all patches.
Wrinkled, ripped, or perforated transfer belt.
Skewed or absent patches

Overall, the only time I look at those 08 modes is if my eyes cannot diagnose it first.
=^..^=

[BillyCarpenter]

Re: Kyocera General Question

I'll be interested in any answers that you get.

On the machines that I know the best: Konica Minoltas, Toshibas, and Kyoceras ...

I guess Toshibas are the easiest to understand the process. If the patches are not in a useable range you'll get CE40, CE20, or CA00, depending on whether it's a fault with the color registration patches or the color density patches. Rarely do we have problems with the patch sensors themselves. Sometimes the shutter doesn't open or the sensor gets dirty, but I don't think I've ever had to replace a patch sensor on a Toshiba. Usually the patch is imperfectly formed for a variety of reasons. In this order of likelyhood:

Poor developing/depleted developer
Dirty grid/scorotron
Dirty laser slit glass
Worn drum/poor drum cleaning
Poor primary transfer belt cleaning
Poorly tracking transfer belt
Laser issue in forming the patch

And all of these can be diagnosed by removing the primary transfer belt and examining the patches on the belt immediately after the code occurs. There are 08 modes that record the number of errors for each color and each sensor. I could memorize all those 08 modes or look them up each time ... or I could just pull out the primary transfer belt unit and see (in this order of likelihood):

Voids in the feed direction through a CMY or K patch
Light areas in the feed direction through a CMY or K patch
Lines of CMYK or composite black in the feed direction through all patches.
Wrinkled, ripped, or perforated transfer belt.
Skewed or absent patches

Overall, the only time I look at those 08 modes is if my eyes cannot diagnose it first.
=^..^=

This is a very interesting to me. I must get up to speed in this area as I don't like using the shotgun method of just replacing things until the problem is corrected. This helps greatly.

I'll let you know the results of my tests. Hopefully, the info. I was given holds true.

[tsbservice]

Re: Kyocera General Question

This is a very interesting to me. I must get up to speed in this area as I don't like using the shotgun method of just replacing things until the problem is corrected. This helps greatly.

I'll let you know the results of my tests. Hopefully, the info. I was given holds true.

I like your approach Billy very similar to mine
I would start reading manuals and theory of operations they are pretty much the same between different brands I think. You must have very good understanding of processes and its components before starting to look at specific values in service mode. That said I think the day when machines will tell all their secrets from just looking at some table with values is far away. We have now PM counters and drive counters but there're so many different environments and obscurities. It's like cars, now they're pretty much all computerized but part failures are way from excluded.

[BillyCarpenter]

Re: Kyocera General Question

I like your approach Billy very similar to mine
I would start reading manuals and theory of operations they are pretty much the same between different brands I think. You must have very good understanding of processes and its components before starting to look at specific values in service mode. That said I think the day when machines will tell all their secrets from just looking at some table with values is far away. We have now PM counters and drive counters but there're so many different environments and obscurities. It's like cars, now they're pretty much all computerized but part failures are way from excluded.

I was a copier tech for many years. But I've been away for about 15-years. A lot has changed since then.

I was given some information by KYO and I'm trying to verify it. The information appears (I'm guessing) to be on a higher level than what a tech is privy to. I'm guessing these readings are used by engineers or tech support to help isolate the problem Just a guess.

[sparkycivic]

Re: Kyocera General Question

I always know that I'm going to have a color quality issue when I see C7620(color registration timing error, hidden from user), and it's usually when the transfer belt isn't cleaning or a drum/developer are dropping toner or otherwise filthy engine.

I also always know that there will be quality issues on 00-01 series bw or color if any charge roller has more than 100K since last engine service(clean). unless they are MCxx20 which are much improved and seem to rarely need attention between kits.

Actually, I don't look too much into the number data of the maint report. At this point, I already know just by experience what needs changing and what needs... other. It helps since I only work on Kyo stuff

[BillyCarpenter]

Re: Kyocera General Question

I always know that I'm going to have a color quality issue when I see C7620(color registration timing error, hidden from user), and it's usually when the transfer belt isn't cleaning or a drum/developer are dropping toner or otherwise filthy engine.

I also always know that there will be quality issues on 00-01 series bw or color if any charge roller has more than 100K since last engine service(clean). unless they are MCxx20 which are much improved and seem to rarely need attention between kits.

Actually, I don't look too much into the number data of the maint report. At this point, I already know just by experience what needs changing and what needs... other. It helps since I only work on Kyo stuff

Thanks for sharing. How many pages on average are you getting from the DR & DV units on the 01-series?

[sparkycivic]

Re: Kyocera General Question

Thanks for sharing. How many pages on average are you getting from the DR & DV units on the 01-series?

Drums are able to get to their rated life fairly easily, they usually end up with a (very) slight density variation pattern in greys that my users never complain about. I can see it when looking at the surface too. It's a bit like those stereogram hidden pictures from the 1990's.

Developers, they are usually pretty much unusable by the time 600K comes around. The coating has worn away, the density of greys will mirror the pattern of the coating which looks patchy, and the spillage will be everywhere inside the device.

[Tricky]

Re: Kyocera General Question

Drums are able to get to their rated life fairly easily

With the original charge rollers? had a 4052 today 200,000 copies most of the charge rollers had small lumps on them producing light spots approx 4cm apart.

[BillyCarpenter]

Re: Kyocera General Question

If any Kyocera tech could post the actual yields that you're getting on the following, I would appreciate it.

1. Drum
2. DV
3. PCR
4. Transfer Belt

[Tonerkiller]

Re: Kyocera General Question

Just run an 089 sample set, before you do anything. Clean the machine, run color reg.,and toner curve. If no copy quality problems or codes, you are done.

[BillyCarpenter]

Re: Kyocera General Question

Just run an 089 sample set, before you do anything. Clean the machine, run color reg.,and toner curve. If no copy quality problems or codes, you are done.

I hear ya but what if I do have an image problem?

I probably haven't put forth the amount of time learning these machines as I should. But that's over with. I've been pouring over the service manual and getting information from Kyocera techs on here. In my limited experience on the new Kyocera's, they've been pretty damn reliable.