Worklog - The straw separation mechanism: A revolver is not only a gun (June 6 2010)
This group is by far the most complicated in this machine. The most difficult part is to manage to separate just one straw. I tried several models with different shapes-configurations. Apparently, straws have a very bad habit:they stuck! If a funnel is to be used, there will be a time that two or more straws will try to go through the funnel and they will stuck. I tried cylindrical funnels and flat funneled surfaces. They all had this problem.
So i completely changed my orientation to the solution. I tried a revolver mechanism. The straws will be inside a tube. At the bottom of the tube, a 4 positions revolver will be rotating. Each position of the revolver will be able to fit only one straw. Under the revolver, there is a cover with a single hole. When a position of the revolver that has a straw inside lyes over this hole, then the straw will fall from this hole.
First i cut out the plates of the revolver from a 10mm plexi-glass
With the conical drill i drilled the revolver holes
I cut 4 pieces of aluminum tubes
That is the revolver assemble
To fix the revolver on the motor...
First i did some M3 threads vertically on the motor shaft
A screw perpendicular on the shaft will secure the revolver. With the dremel i engraved the shape of the screw on the bottom plate.
Finally, on the tops side, i cut an aluminum piece with 3 holes. The middle hole will be used to screw it on the motors shaft, while the other 2 holes will screw this piece on the revolver piece
A commutator out of garbage
Now i need to have a vibrator on te revolver to help the straws go down the pipe. The problem is that the vibrator must be fixed on the revolver - which rotates! So i must make a commutator for the power supply of the vibartor:
From an old cassette recorder/player i removed a small limit contact
on which i soldered only i wire on both pins
I grooved a pocket for the contacts to fit in at the bottom side of the bottom revolver piece. I glued them with hot glue
Now when the piece is inserted onto the motor, the two contacts will touch the shaft of the motor. This is the first pole of the commutator
The other pole:
From a tin can i cut a round (approximately round) ring
I soldered a wire on this ring
And then i glued it on the base of the revolver - the statro
Now to pass the current to the rotor. First from the ring to the rotor:
I made a hole with 2 diameters. The big diameter is a little bit larger than a metal ball that i will use, while the other fits a wire
I passed through the first vibrator wire through this hole and soldered a washer at the end
This is the metal ball with a tension spring. The ball comes from a vandalized ball bearing and the spring from a (same situation) power relay
The washer is at the bottom, the spring follows and then comes the ball. The ball now is always pushed against the ring on the stator
The other wire for the vibrator come from the shaft itself. The wire is connected on the screw that is fixed on the shaft, to hold the revolver on the motor. The vibrator is just a motor with an eccentric weight:
Then, i fixed the vibrator on the top piece of the revolver. I also put a thin cover of white plexi-glass with smaller holes for the straws. This is the finally assembly of the revolver:
Puting it all together
The revolver must be inserted into the tube where all the straws are. So, i did 4 holes on the tube and the revolver base (stator). The motor of the revolver is fixed on the base. With 4 screws, i screwed the revolver base on the tube:
I did 4 holes on the tube and the revolver base
With 44 screws, i screwed the revolver on the tube
This is how it looks like from the top side of the tube
@Alex In Greece during the Ancient times there was this saying: "Oyden monimoteron ek toy prosorinoy" which means that "nothing is more permanent than the temporary".
But now that you said that again, i think i should restart this project, shouldn't I? Hopefully within this year.
Hi you have a nice coffee Instant Cold Coffee Machine but you wanted to use a fridge for cold water but no water cooler that you use waron also in coffee automaaten is where you can get I know old water out of if not the name but it can look for you we have that built-in devices greetings alex
Hello George. Regarding the elements, these are hardware wiring to indicate wire connections between the modules. The orange boxes indicate wires coming from the output module (Digital Output Module - DOM), and the green indicate wires going to the Digital Input Modules. Notice that for example, from module "Rotary table", 4 wires comes out, then 2 of them arrive from the DOM and 2 goes to the CPU.
As far as the diode is concerned, this is only for polarity protection. It is the same as the D2. But you are right, It is not necessary and i may not put it after all.
I think your architecture diagram (first figure) is slightly confusing, because it seems to include elements of code (the elements above the CPU) with hardware elements. Ideally, you would have a system-level block diagram detailing your hardware and a separate functional block diagram to describe your code. If I'm misreading your architecture diagram, feel free to ignore this.
Secondly, looking at your reset circuitry, I see you have a 1N4148 diode between your microcontroller pin and your ICSP header (pin 1). I'm fairly certain this diode is not necessary, so you may want to double check that.
Frappé has become very popular here in the States. The difference is we use fresh coffee grounds to make coffee then we chill the hot coffee. But we tend to make more fresh coffee here while Europeans tend to make more instant coffee.
To serve we pour some in a glass and add chipped ice.
We also tend to add flavors to our frappé in the States. We can't leave a good thing alone - we have to tinker with it to make it more sellable.