So, I am working on a project where a homemade railroad car goes on tracks through the bar. Homemade, 12V motor cycle battery driven - seems to be working so far.
It goes with several glasses that should be filled with whiskey. Position of the glasses beneath the bottle I have control of.
My question is: Which is the best way to dispense the whiskey?
I have tried using a solonoid, connected to the bottle (through various couplings). Does not work - no air can enter the bottle, so nothing is dispensed. I kinda got around this by having an air-pipe go out of the bottle, through a T-pipe above the solonoid. Not preety, and not reliable. Perhaps I am doing it wrong...
Another alternative would be to have the bottle in something like this:
Then have something push up on the "trigger" to have it dispense whiskey. Will probably not raise the glass, but something like that.
What other options can you see? The mechanical parts of this projects is by far the hardest for me - coding is much easier for me than making the rest of the stuff. But that is what makes it fun
I don't know, but I think that they can work for you too.
I don't understand one thing. When you say:
I have tried using a solonoid, connected to the bottle (through various couplings). Does not work - no air can enter the bottle, so nothing is dispensed.
This is when the bottle is upside-down? And with a hole (or a piece of tube) to "feed air to the system"?
The liquid only touch the inside of a tube, so only that tube need to be food safe, and we have more that $100 of difference I believe, for a piece of tube?! BTW the tube can be exactly the same.
What an awesome idea with a pump - had not thought of that at all!
It seems that I can replace the hose from the pump suggested by Luisilva - so should be able to make it food safe. The pump from LarryD may be the more safe way to go - but the price difference is a bit too much for me...
Would also remove the risk of a failed seal causing spilage. Would be limited to "pure" liquids only though as I see it - many types of shots are quire sticky, and would clog the pump almost immediately - or..?
luisilva:
Nice idea! Can I have one cup?
Any time
I will be posting pictures and more once I get to a working solution - both of train and dispenser
luisilva:
I don't understand one thing. When you say:
I have tried using a solonoid, connected to the bottle (through various couplings). Does not work - no air can enter the bottle, so nothing is dispensed.
This is when the bottle is upside-down? And with a hole (or a piece of tube) to "feed air to the system"?
It is hard to describe what I mean, here is a drawing:
The inner tube is my try to allow the bottle to "suck" air, as the solonoid is open. It works most of the time, but not consistently - perhaps air is entering the inner tupe as I am loading it, or similar? Note that the outer tube fills with whiskey to the level as in the bottle - unable to seal it.
It is worth noting that the inner diameter of the solonoid is smaller than that of the bottle, which may be why opening the solonoid alone (withou t-junction) is not enough for it do dispense anything?
I kinda liked the idea of the solonoid to begin with, so suggestions on how (if possible) to make it work, would be appreciated
Henry_Best:
Raising the glass is the usual way.
Agreed However since the train cart contains 4 glasses, implementing an ability for each of those would be quite difficult.
I am thinking instead fo attach a servo to the "Optics", so that I can that way raise it, as if a a glass did the same. I am not quite sure how to mechanically attach that, but it is probably possible.
Thanks! I apreciate your suggestions - it is so much fun to work on a project such as this
You are helping me. What I was trying to say is that the 2 pumps can work with only a tube "Food Safe". We don't need for this application a very specific pump but only a very specific tube.
luisilva:
You are helping me. What I was trying to say is that the 2 pumps can work with only a tube "Food Safe". We don't need for this application a very specific pump but only a very specific tube.
I am not entirely sure of how such a pump works, but wouldn't the fluid always have contact with the "fan blades" inside of the pump? I am by no means scared of the food safety, but thinking that the blades/spinner would be the weak point in this case?
@Hotcut: No. I have 4 in a little project here in home (for a hydroponics controller), and no.
You can find the way they work if you "google" for peristaltic pump. Here some images for such a search:
luisilva: @Hotcut: No. I have 4 in a little project here in home (for a hydroponics controller), and no.
You can find the way they work if you "google" for peristaltic pump. Here some images for such a search:
That's cool - such a simple way for it to work - never heard of that before.
But that does indeed make it much more clear how it works, and how easy it is to change the tubes to food gradde, and if/when they get dirty. Would mean I could use it for virtually any kind of liquid, even if it is sticky, as I could just change tubes every now and then, if sufficient cleaning is impossible. Cool!
Only thing I would need to figure out, is how to seal the bottle when not in use - preferably without taking the tubes up of it. No fun in dust getting in, and alcohol evaporating. But would still need to allow air to get in when pump is on.
It sounds like overkill to have a T-junction with the pump on one side, a solonoid on the second and the bottle on the third. When pumping, solonoid is opened to allow air to get in. It could work of course, but is it the best way? Seems like a lot to have a solonoid "just" for that, no?
I have just ordered the pump - downside is that it will take a month or so to arrive, but will let me have time to work on the trainy part of things Just waiting for additionally 4 stepper motors for that though It will be running with 10 stepper motors; one for each wheel.
Only thing I would need to figure out, is how to seal the bottle when not in use - preferably without taking the tubes up of it. No fun in dust getting in, and alcohol evaporating. But would still need to allow air to get in when pump is on.
It sounds like overkill to have a T-junction with the pump on one side, a solonoid on the second and the bottle on the third. When pumping, solonoid is opened to allow air to get in. It could work of course, but is it the best way? Seems like a lot to have a solonoid "just" for that, no?
Optics will solve all of this for you - you just need a mechanism to open them - as in the link I posted earlier.
wildbill:
Optics will solve all of this for you - you just need a mechanism to open them - as in the link I posted earlier.
I completely missed that post from you before - sorry about that. Quite an interesting take on it indeed - does seem simpler than using a pump, solonoid or any of that.
Opening mechanism would be the "only" home-made mechanical part of it.
I like it
So many interesting ideas and thoughts in this thread - thank you all! Ideas regarding the pump and sealing etc. would still be appreciated - if nothing else, then for the interesting part of it.
Hotcut:
(...)
Only thing I would need to figure out, is how to seal the bottle when not in use - preferably without taking the tubes up of it. No fun in dust getting in, and alcohol evaporating. But would still need to allow air to get in when pump is on.
It sounds like overkill to have a T-junction with the pump on one side, a solonoid on the second and the bottle on the third. When pumping, solonoid is opened to allow air to get in. It could work of course, but is it the best way? Seems like a lot to have a solonoid "just" for that, no?
(...)
luisilva:
I think that what you need is called "non-return valve":
...
The liquid and/or air only goes through in one way.
Right you are - the simplest way to do things, is often also the best way
One has been ordered and is on the way.
Thank you all - soon summer vacation is upon me, and I will have time to play around with this
Thank you all for the great ideas, suggestions and information.
Just waiting for additionally 4 stepper motors for that though 
It will be running with 10 stepper motors; one for each wheel.