Feeders for my surface mount machine



 I have a pick and place machine for placing SMD parts, at some point last year I ordered the parts for a new project and it used quite a lot of "oddball" components.  I didn't really notice how many until the reels turned up. Unfortunately, it was more reels than I had reel holders (feeders) ...


 

 I had a few more in a box somewhere, but those were mostly my rejects so I managed to order a few from the USA at a good price.  Unfortunately what turned up from the USA was mostly marked "faulty" or "occasionally jams", "misses steps" and other encouraging words. I was at best dubious about getting them going and the few I tested did indeed appear to be faulty. These things are notoriously tricky, they use compressed air and a small cylinder to actuate levers and ratchets and if any part doesn't perform perfectly, it will not correctly advance the components. Gloom set in. 

Christmas came and went and amongst the festivities I found a chap in the Frozen North (well, Lytham St Annes) with some feeders for sale at a sensible price. A quick(?) trip up the M6 and I had I had another 30 feeders and some more IC "stick feeders", happy days ... except these didn't look great either. 

Over new year I sat down to sort these out, I'll probably end up going through all my feeders as I have learnt a lot more about the faults and adjustment of these things. 


There are 2 minature "sprag clutches", one in the waste cover tape take up system, a second inside the feed roller, plus a ratchet-pawl system on the feed roller. These have to work perfectly, disassembling and cleaning them seems to sort them out. The ratchet-pawl often is clogged up with old, hard grease, this has to be stripped and cleaned. The air cylinders need a dab of lube and the end-stop has to be adjusted to correctly move 2 ratchet stops on the feed roller.

 Once that is done, the actuator button has to be lubed, the screw tightened, the metal strips which act as guides for the component tapes have to be carefully bent and formed to ensure they track the feed roller in a smooth and close fitting curve ... Finally, the two airflow regualtors have to be adjusted to give a crisp, but not violent response, I think I might get a flow meter to help set those up, as currently they are a bit random, but certainly a lot better than when I started out.

By the time its been disassmbled, cleaned, adjusted and checked it takes around 45 minutes to do one properly. I must have spent 2 good days (well, evenings until 2am anyway) on this so far and have around 25 done.  I think in total I have around 70 standard 8mm feeders now, which is pretty much a fully loaded machine, plus some weird ones (like 12,16 and 24mm) I may just press on and service all 70, as once the serviced ones get mixed in with the rest it's just going to get messy, wish me luck.

If you want a tedious video of the machine in operation from when I first got it ... 



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