Feeder question

[smt-user]

Hi

Recently i bought a RV4 machine with 8 feeder units .
As i checked there are some problem in some lanes .
The first  one is  that 2 lanes in an 10x8 mm feeder are not pulling the plastic tape
corectly so it prvents the nozzle picking up component .Anyone can guide me what is the reason?.
Can it be fixed and how ?
The second is that 2 other lanes are making a strange noise during indexing and sometimes component
is not indexed correctly .The indexing sounds not so smoth as ther lanes . Any ideas ?
Is it possible that some components have fallen inside the feeder mechanism and are jamming it ?.
Is it easy to service the feeders ? Do we need special tehnician ?.
As i understood the best  operation is if you assign feeders to jobs .So where can we buy extra feeders?.
ANy indication  about price?
Any video as to how feeders can be serviced or any instructions?.
Sorry for asking so much but i'm kind of lost here

[Gopher]

Ok,
Parts can and do fall inside these feeders, I have never had it cause a problem however as they have typically fallen to the bottom.
The index mechanism is very basic, all the indexing pins are little solenoids mounted on a tray, the tray is driven forwards on a rack and pinion so an index operation involves pushing up the pin for the relevant lane and then pushing the tray forwards. IIRC the is a little screw  at each end of travel that pushes a microswitch to set its limits. I wouldn't be at all afraid to take the side off a feeder and take a peek, at a guess weird noises during travel could be parts in the mechanism or the rack and pinion could be worn. However even quite an old feeder that I looked inside showed very little wear.
If the cover tape is not being pulled off properly, you are looking at the belt mechanism on the top of the feeder, if you look in from the back you can see that each one is sprung loaded and there is a screw to increase the pressure it applies to the tape travelling beneath it, not enough pressure and the tape will not drive the belt, too much pressure and you will typically see the component index forwards and then spring back. These belts do wear out, IMHO they are probably good for less than 100K indexes each. Replacements are discussed here http://electricstuff.co.uk/forum/index.php?PHPSESSID=f57f1939d6c1676fe58b10c1c56b88d5&topic=132.0 I think I eventually decided 84mm was a bit too large, so you would probably want something a little smaller but they certainly worked. Replacing these is fiddly as you have to remove that whole bit from the feeder, whereupon it becomes a floppy mess of springs and belts. While its off, probably a good idea to give everything a good clean, getting the assembly back on is the tricky part, there are no tips you just have to suck it up and get on with it.
Having dedicated feeders for every products is a common solution for any machine where set-up time and job turnaround is paramount, the idea being you just switch in feeders with the parts you want and you are good to go. Not sure about the benefits when you are not going more maximum throughput however. You shoould be fine with having as many feeders as your biggest job needs, or perhaps as your two most different ones need in combination...
Feeders should be £350 each or less I would suggest. Grove often used to sell them and sometimes EPS.

[Mike]

If you have feeders of unknown origin it is well worth the time to strip down, clean and replace all belts. It's a fiddly job so best to do it all in one go. No special skills, just figuring out the "knack" of getting it all back together with teh spring tension. Expect to swear quite a lot the first few times you do it
Also check the adjustment screws - don't be tempted to just keep tightening as this can be counterproductive & chew tapes.
After a re-belt, set them all fairly slack and tighten just enough to feed reliably.
There is a post here about standalone bench-testing feeders which can be more convenient. 

[smt-user]

Hi

Thank's for all the answer guys.I could not though find a solution so i made a video showing this feeder problem .
I hear a clutching sound not smooth as other feeders .ANy ideas? .My first thought is the stepper motor .It seems
to miss steps .

[attachment deleted by admin]

[Mike]

I've had issues in the past with the connectors going intermittant - a dodgy pin on one of the stepper connections could be the problem. Or a dead output on the stepper driver - should be easy to see on a scope.

[William]

I have a colleague who used to do back to base repairs on the feeders and or do exchanges etc. Not spoke to him in a while, I will see if hes still at it and post details if its positive. He always said it was fairly straight forward. I guess we must have been lucky... didnt have too many issues. Comp jams pretty common on other manufacturers kit also.