Adf Jams

[CableGuy]

HI all
I'm having a small problem on a DF611 on a C253. Originally I was having problems with it jamming in the transport area, just as it got past the glass, to the next set of rollers. It would stop and there was a small crease across the direction of travel. I eventually overcame this problem by adjusting the spring under the sep roller to it's lowest position. That worked fine for about 6 months. I got a call yesterday to say it is multi feeding on a certain preprinted letter head when put through the adf. It seems to be fine on regular 80gsm, but plays up with the other paper. My problem is, that when I adjust the spring under the sep unit to counter the multi feed, the old problem comes back. I will order a new sep roller, but it has only done about 20k in scans. Can any of you, my wise old friends, perhaps enlighten me with a solution before I go 'postal'......

KM's are not my friends!!

I thank you in anticipation.

Just a foot note, I did apply all the fixes that the nice guys at the tech support centre originally suggested, to no avail.

Thanks again

[chexin51]

DF-611

Yes you are stuck in the middle of 2 problems. I also have been forced to put the lower sep pulley spring at the lowest position in order to pass ordinary paper. You might have to change the upper and lower roller together as they really work together. You might try ventilating his special paper originals before passsing them through the feeder. Try them backwards as well. Did the special paper originals just come out of a printer and now they want to make copies. Warm and/or curled originals from some printers can be problematic in themselves.

On page 2 of the DF-611 Service Manual Section E. "Paper feed not guaranteed originals" - a list of original paper types that can feed but "trouble occurrence will be possible" is "Sheets with rough surfaces ( e.g., letterhead)" lets you know that there are some types of paper that can be problematic and there is no solution. I bet you didn't want to hear that but that's what the Service Manual says.

[pepper38_cnd]

There is a note on the SSD to trim back the mylar on the sep pad, I have found Replacing sep roller, torque limiter, and the sep pad with the mylar trimmed back to the glue line works.

[CableGuy]

Thanks Fella's, I have ordered the replacement parts and will give this a try.
Cheers

[CableGuy]

And here we go again. The blasted machine is still giving issues with adf jamming. Are these machines just rubbish at feeding paper through an ADF? Some time towards the end of last year I replaced everything in the adf that looked like a roller and some other bits. It seems to behave for a few months and then the same old problem re-occurs. Bearing in mind that this machine is in a rather small office and is a very low volumne machine. Thankfully I have fewer of these machines to look at these days, and will be a happy man when I don't have to look at a KM ever again. When I compare them to the Ricoh machines, they generally feed anything that is thrown at them.

So is there anything I should know about these, any little heads up would be most helpful.....OK rant over....again....

[Stirton.M]

Generally, I have had very few problems with this series doc feeder. Cleaning and regular replacement of the rollers is usually the majority of what I need to do. We have several thousand of these out there and they all work more or less without issue.

I usually change the clutch that comes with the unit to the black one (if this is the doc feeder I am thinking of that comes with a white one). A small modification notch to the metal plate that holds a sensor in place to allow the black clutch to spin freely finishes that up.

I also change the rubber of the separation roller to the red rubber seen on the feed side (pop off the rubber from the spindle and swap).

Another mod is to trim back the pre-sep mylar, the part that is not glued down.

A mod that some of my peers have been doing that I personally do not see any value in, is to increase the spring tension of the feed roller springs, by stretching them a couple rings in to increase the tension. It is partially related to the following.

In rare cases, the feeder may have an elevation problem and pop a series of C codes related to this. In those cases, two modifications are performed, one is relatively simple, place a somewhat thick mylar on the bottom side of the tray where the cam lift plate pushes against it. A millimeter is more than enough thickness. A second mod, should the codes persist, is to replace the lift motor assembly. A symptom that is obvious of this problem is if the tray moves up and down on the last couple pages in any given scan job.

Also ensure that the paper sensor felt pads are clean and black. There are two, one on the left cover, the other on the paper guide just before the paper goes across the glass.

And of course, it goes without saying, if the document feeder is not sitting flat to the main body, all sorts of problems will persist with jamming regardless of the above.

There are four protrusions on the bottom side of the doc feeder that set the height. If any are too high or two low, skews and jams WILL occur. The height adjustment screws on the hinges adjust these. I shine a flashlight into the crack to see where the rear protrusions are sitting and adjust the height according to those. You can slip a sheet of paper there to "feel" if the protrusion is sitting against the top cover of the scanner. The front two should be sitting flat if the rear points are set correctly. If not, the adjustment needs to be done. Keep in mind, the front two corners are adjusted by the diagonal (opposite side rear) screw. Be sure to adjust for skew correction after performing this (via right side hinge), and then perform the manual stop adjustments using the adjustment chart.

[CableGuy]

Stirton, you're a gem as always. Thanks for the info, I'll look into all of the above. It seems that the major symptom, after interrigating the customer some more, is it doesn't seperate the pages, this sometimes causes a paper jam. Other times it just sends two pages through without calling up a jam, but the customer can physically see this happen and of course it is missing a few pages in the documents, scanned or copied.
I've been down there and tweeked the adjustable spring under the sep unit. It's on it's lowest setting, I can't put anymore pressure on the spring(i.e. the middle or upper notch) as it then refuses to feed at all then. And the feed rollers and other parts in the adf were replaced late last year and have about 20k on the now.....

I must say that usually the adf is the only thing on a machine that works no problem, it's the other way around on the KM's....?

Cheers

[Stirton.M]

As I've said, I rarely ever have problems with the doc feeders since they changed to slit glass technology, usually just basic maintenance. Why you are having feed issues like the ones you describe is usually due to the examples I described above. Multi-feeding is no surprise if you are set to the lightest pressure, but why it jams when you have it at medium, I am not sure, aside from suspecting a worn out clutch (one way bearing) and shaft. It could simply just be a lemon doc feeder.

Out of curiosity, when the unit jams, what are they feeding? Does it have dog eared corners, excessive curl, or hole punched. No doubt you are aware that scans can be performed using the opposite edge and setting document original direction in those cases, it is highly recommended, not to mention to fan the paper if it has punched holes. Those are notorious for feed issues.

Also, what kind of jam codes do you get when the sep pressure is set to the middle? And is the paper making it to the feed path, or is the sep/feed tires preventing the paper from going further?

And while I think of it, the sep assembly itself, the metal plate with the presep rubber, is the portion of the exposed rubber sitting flat against the plate or is the glue underneath losing grip and the pad is no longer flat? If so, remove the plate from the assembly to make it easier to handle, carefully peel the pad (with mylar attached) completely off the plate. Clean the exposed tape if there are bits of dust and debris, a little isopropyl or methanol on a clean cloth, lightly rub it to clean off that dust, but try not to damage the sticky tape. Or simply replace it with new double sided tape if you have any. If you cleaned it, let it sit a minute or so for the alcohol to evaporate and then restick the pad to the plate. There is a notch on the plate surface to help center it, line up the two outside corners to the edge of the plate (there should be a couple millimeters of pad extended from the plate). Be sure to secure the pad portion first (and make sure it has good adhesion) before sticking the mylar portion down. Try not to 'stretch" the mylar or it will eventually pull the pad away as before. If all goes as planned, the plate can be reattached to the sep assembly and installed back into the feeder.