I work in a brewery/contract packaging buisness and i need to add an eye to our line. We make an energy drink for a customer and it has a sleeve label on it. I dont know if anyone is familiar with this type of label, but it comes on a roll and is shot over the bottle then ran through a steam tunnel to shrink the label to the contour of the bottle. If the bottle has moisture on it the label will not go all the way down before entering the steam tunnel. If this happens, the label sticks up about an inch over the top of the bottle. That is what i would like the eye to see. If the bottle gets into our filler (24 head 2x vacuum Sasib), the excess label sticking up gets cought in the fill head and destroys it costing us about $200 bucks a whack and an hour of down time. The sensor doesnt need to see any color or anything fancy, just if there is anything sticking out the top of the bottle. When it sees somehitng, i would like an alarm to go off, or eventually have a pneumatic cylinder push the bottle off the line. I have some extra photo eyes around here. Im not sure if i need a whole new PLC to do this, or if there is an easier way to make this happen. I have an old Allen Bradley PLC (AB-PLC 5/20) with a handfull of I/O units on it that were not using. If anyone can help me get this started it would be greatly appreciated. It SHOULD be pretty easy, i think but im not sure. Thanks in advance.

I dont need to use the AB PLC, and quite honestly, would rather not. I COULD reporgram the PLC used for the whole bottling line/filler, but that seems redundant just to add a photo eye and an alarm. Is there any easier way to do this other than reprogramming the PLC?

Eric Noe
LiquidMFG

[email protected]

 

Hello Eric,
Of course there is the possibility to do it without a PLC. But if you do not stop the line in any way, I would think it is better to get the bottle off the line.

If you use a regular photo eye, the output of that should be sufficient to drive a standard relay with multiple contacts. This relay can hold itself powered with a contact in parallel with the photo-eye output. That way another contact of the relay can sound the alarm, activate a light becaon, etc.

With a normally closed contact of a pushbutton in series with the relay coil you could reset the alarm etc. again.

If you want the bottle pushed off the line, you do not need the relay to hold itself powered, no pushbutton. A contact of the relay can power the solenoid of 3/2 valve which can send air to a piston that pushes the bottle off the line. As soon as the bottle is off the line, the photo eye is no longer seeing the sleeve, the relay goes back to the unpowered state and so does the 3/2 valve, allowing the cylinder to retract and the belt is free for other bottles to pass. If you want, you can send me an email to theo dot baarslag at wxs dot nl.

I can then reply with some sketches to make it more clear.

KR,
Theo Baarslag

 

If you are just using the sensor to sound an alarm, you don't need to connect it to a PLC. A timing relay would however allow you to control the length of time the alarm sounds for (use it as an extended pulse timer). If you decide to do it this way, you may want a second sensor further down the conveyor to shut down the conveyor if the bottle makes it that far.

If you install the automatic bottle ejector, you will need to use a PLC. You will need to connect the bottle sensor, "extended" and "retracted" sensors on the ejector cylinder, a sensor to tell when the reject chute is full, and a beacon to tell people there are rejected parts in the chute waiting to be removed. You will also want to shut down the conveyor if the ejector doesn't remove the defective bottle from the conveyor. The above can be done with relay logic, but it is easier to just use a PLC.

You may wish to try to remove the bottle from the line at the label applicator, and before it reaches the steam tunnel.

 

If your labels have UV in them an UV sensors will work the best to see the labels

Regards;
Craig Blondin

 

Eric,
I work for a company called Karlville and we specialize in shrink sleeve equipment. You could incorporate a rejection system with a camera to eject all faulty labels that don't meet a predefined template within a tolerance onto a rejection tray. If you need any information don't hesitate to contact me.