plc labeling machine components help

I am starting a new project which will basically be a labeling machine. I have been buying all my components from automation direct but they don't sell one thing I need. I need some kind of label sensor that can detect the edge of each label which are on a big webbing roll. They are just 2" square white labels with a little writing on them. I did a lot of Google searching and found a couple that say they use m8 or m12 cables, but I don't know how they are supposed to connect to my plc. I would like to be able to have the sensor tell the label motor when to start and stop so the timing doesn't get off. Things just not something I have a lot of experience in.

I appreciate any help in advance. Any kind of 7no will be a big help.

Do a google search for sick sensor. They make a good one
Labeling machines are pretty complicated
Can you describe in detail how the machine works?
The ones I worked on used print mark registration and had to cut the label at the print mark

Use a "slot sensor" like this : http://goo.gl/uk5Yf

Many more out there, I've used Omron also in the past

For label sensing, I have always used Lion Precision. They work VERY well...

http://www.lionprecision.com/label/index.html

I would save the aggravation and just buy a commercial labeller (I like Herma). Quite a few years ago, I retrofitted a few older Quadrel labellers with PLC controls. I reused the existing stepper drivers, and controlled them with CTRIO modules from AD. It wasn't easy, which is why I would recommend buying an off-the-shelf labeller. No need to reinvent the wheel...



-Eric

labeler

Luckily this is not a project I have to do for anyone. It is just an idea I want to play with a little. I am an engineer at a patio cushion manufacture. Right now we pay employees to do nothing but peel and stick price labels and put them on the law labels of every cushion made, About 16, 000 a day. My idea is to make a machine that can position one label at a time on a conveyor and either make a labeler or buy a labeler that will stick the price labels automatically on each label. The price labels are 2" square and come on rolls that have about 2000 labels on them. The roll is only one label wide, so each time I advance the roll, it would only stick one label anyway. I have a bunch of equipment that I can do testing on now. After I do some initial r&d and I am somewhat successful, I might take the idea further into some working prototypes.

I'm a more than open to any ideas you guys might have for me as well.

Question. What would you normally connect the other end of the cable on a label sensor? Are they just stand a lone device or are they designed to hook up to a programming device like a plc?

The label sensor would be used as a registration input. This is used to correct any error in the label feeding distance. See the attached example application from TrioMotion, specifically the 'Label Feed' explanation on Page 3.



-Eric

Are there any other alternative sensors that can detect the spaces between labels and most of all be easily compatible with a plc? I don't necessarily need this to be a lightning fast machine. If there is an alternative that can work almost as good I wouldnt mind looking into that. The labels come on Silicone Release Paper so its sort of semi translucent. The labels are solid wight. I wonder if some kind of light sensor shinning through the paper would work?

Have not used it but.... Label-Eye from Tri-Tronics
http://www.ttco.com/industrial/label-eye.aspx

I have used a Leuze GK 14/24 L sensor in the past, for the detection of transparent labels. it worked very well. it detects the thickness of the label.