Need some electronic engineering smart peoples help!

[Crut]

ok all you smarties out there, i got a riddling project for ya.
As a side job from brewing, I help my long time best friend on his fruit farm, and as many of you know, its apple cider pressing time. He is one of the only farms in the area that doesnt pasteurize, and makes the best cider around, ask around and youll find that out. Its not a big operation, but i told him id help shave some time off his cider'in days. We usually press 300-400 gallons per press day, clean up, the jug it, by hand. Id like to figure out some way that we could hook up a weight sensitive scale that would shut a valve when the gallon/half gallon is full. The fill taps are similar to the faucet thats on your bottling bucket.
any of this make sense or only in my mind.
So basically i want to put a empty jug on a scale, hit a button, jug filles to a set weight of cider, scale tells valve to sloe, remove jug, screw on cap, and done.
Anyone know of where to get any of these materials and how to rig/wire it up? im looking to have a 2, 3, or 4 head filler.
Thanks all-cheers
-Curt

[Padronis]

All I can think of are the ghetto ways to make something that would work for you. I don't know where to search for any kind of "weight sensitive switches" or weight sensors. I would imagine it would be PLC controlled (unless you go ghetto like me). Maybe you could even use some kind of light sensor to stop the flow at a certain fill level on the jug. Either way, you will need to control the flow with a solenoid to close a valve. This kills me because I can see the electrical schematics in my head but I don't know what physical components to use. Sorry to not give any good answers.

[Weenie Boy]

Just a quick question for you. As opposed to having a scale base switch, have you thought of a time based switch that can be calibrated to fill based on time rather than weight? It seems as though this setup would mimic professional bottling lines and be cheaper.

Just thinking about a solution.

Weenie Boy

[Crut]

Just a quick question for you. As opposed to having a scale base switch, have you thought of a time based switch that can be calibrated to fill based on time rather than weight? It seems as though this setup would mimic professional bottling lines and be cheaper.

Just thinking about a solution.

Weenie Boy

I thought about that, but ive been helping him for years, and learned a few things. Our "holding" tank isnt seal, more of a dual lidded dairy tank, so no pressure is applied, just gravity, and as the volume gets lower, the time to fill a certain carrying vessel is increased.

[Mylo]

I'd do something mechanical - there is less to go wrong. Basically have two, 1 gallon holding tanks. Hitting the valve drains one holding tank into your jug (and shuts supply from the main), while the other one fills from the main. Flop the valve, and the second one drains while the first one fills.

Then you can swap the holding tanks for two 1/2 gallon tanks.


Mylo

[Weenie Boy]

I do like Mylo's suggestion. This is a tricky little issue, isn't it?
I shall continue to ponder this over several beers.

Weenie Boy

[beltbuckle]

If you go electrical, you have three basic options:

[*] Cutoff at a weight limit
[*] Cutoff at a time limit
[*] Cutoff at a volume or liquid level limit

I can think of lots of very cool and slick ways to do this, but the problem is it would probably cost thousands of dollars for the various sensors and such which is probably not in the budget.

So one of the cheap ways to do it is with some electro-mechanical method.

Float valves, purely mechanical, would be an easy solution but finding an off-the-shelf one that would fit in the opening of the jug would be a problem.

But if you had an old balance scale (or made a crude one out of some metal scraps), with the jug on one side and the correct amount of weight on the other side... when the jug was full the jug side of the scale would drop and the other side would raise. You could have an electrical contact that the scale would touch when it hits bottom. This would send power to an electrical valve that would stop the flow.



Probably better to do the inverse and use a normally closed valve but you get the idea.

[Crut]

i like the old school weight idea, ive been thinking about that, but therres gotta be weight sensitive electrical measuring device somehow. Or i may have to mcgruber a old school scale somehow.
-C