Linear Motors and PLC's

[sbrown2]

Can ask how many times does this fault occur, lets say per 1000 bases?

 

[sbrown2]

I worked for N.........n Foods manufacturing pizzas? I'm scratching my head trying to remember this process. I can understand your theory. Was the process designed for the larger bases? If so depending on the failure rate I would want to assess is the product varying in some way so that it is rejoining during the process or is it not being cut correctly? Is this a maintenance led containment you are putting in place or has the maintenance department raised a CAPEX for the euipment you are aquiring? And from your initial posts can you confirm are you replacing the current process or adding a countermeasure if the current process doesn't work correctly?
I assume you have contacted the machine manufacturer but if you still require the modification it sounds like a good idea. Depending what resources you have a dedicated card for your encoder can be acquired but if you are short on funds you can always wire encoders to your inputs if you have spare. What keyence system are you using. I've currenly use the, now aging, CV75 1P which is mainly used for colour recognition but in your environment could pick up the edge of the dough ball. I think you have had sufficient information relating to cutting of the dough balls.
Anyway good luck and my conclusion follows silva fox, find the source of the problem.

 

[netblindpaul]

gerard,
With the correct equipment a flying shear would solve your faults.
However, I have to agree with the others, you really need to address the root cause!

 

[silva.foxx]

So you have a circular plattern that presses down on the dough balls... what about a skirt around the plattern, tapered out and sprung... the plattern then presses down the dough and the skirt prevents excessive spread.

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[gerard]

Can ask how many times does this fault occur, lets say per 1000 bases?

It happens enough to require a person to monitor the products and separate them manually. We want to automate the process.

 

[gerard]

Thanks for your response. This is a project from scratch. At the moment we are cutting them at the end of the line, but, at this stage the pizzas are 'par-baked'and the waste cannot be recycled. So, we are trying to cut them before they enter the oven and recycle the dough at this stage, where it is easy to do so. The machine manufacturer would be of no use to use us, because, as I said, this is something we want to do to reduce waste ourselves. It is not easy to resolve the problem from the source - the dough balls are free pressed and are never the same size or shape. I know this sounds a little crazy, but that's the process and we just got to work with what we have. I am not sure of the Keyence system yet as we only trialed it and the guy seems pretty sure it will do the job - and I am not up to speed on it yet. To sum up, we are looking to cut the pizza bases, by some method, where the bases are constantly on the move on the conveyor.

 

[Knobhead]

If you can recycle the dough at the detection point then a drop flap makes sense to me.

I’ve worked on faster systems than yours (you may have guessed I’ve seen a pizza line in full production) the belt suffers no slow down. I’ve worked for the biggest chip manufacturer in the UK (sorry can’t say who) but the drop flaps worked brilliantly.

 

[sbrown2]

I am sure the plattern idea silva fox mentioned may be what was used when I was in this industry.

 

[netblindpaul]

Well the flying shear works at Cadbury Bourneville factory quite well.
I believe Sivaa's plattern idea would work too.
As Tony says if you can recycle 100% at the point of detection, then just do that drop the dodgy bases onto another conveyor and set up an automatic re-work loop.
I have also worked on very fast production lines and done design and applications engineering for an equipment oem on this sort of kit, where we HAD to help the client sort these sorts of problems out.
Along with working as a production line staff engineer tasked with cost downs and speed up's on production lines, so IMHO the advice you have had so far sounds good to me.

 

[gerard]

Silva.Fox - we have a platten with exactly what you have suggested and it does not work - In theory it should. We had circular plattens supplied with the machine. The dough ball is indexed to the center of the circular platten and then it presses down on the dough ball - making it round. But, it is not a good design and the dough gets stuck to these plattens and causes all sorts of problems. We have tried this and it's a non-runner.

 

[gerard]

Tony - what's a drop flap - have you any links on this?

 

[Knobhead]

Will try and find out who made them

View attachment 7351

 

[Knobhead]

Should have added travel is right to left. For pizza’s the drop distance only needs to clear the 3[SUP]rd[/SUP] section.
As I said if you can rework the dough it’s a simple way around it.