I want to build a counting machine. I have a small factory of "salgados " here in Brazil. Salgados are small deep fried snacks.
Here are some photos:
As you can see the salgados have different shapes ( round, drop, square...) and they have aprox. 4,5...5 cm long.
What kind of Counter/sensor should I use?
Now the Salgados are hand counted and packed. This take too long and would like to make a small counter to drop 50 Salgados and stop. Then the employee seal the bag and do it again.
I don't know how the factory drops the product into the bag or how you production line looks, but maybe you could use a break beam sensor? It can count +1 everytime a product drops in the bag and breaks the beam. Of course, this requires that all products drops one by one.
Probably the most simple would be an modulated IR "beam" interrupter. A IR LED on one side and a IR detector on the other side with the snacks dropping or passing through the beam. Put the IR LED in a tube to make the beam tighter and directional and the sensor in a tube to shield it from the ambient light. Modulate the IR LED light to make it easier to differentiate from ambient light. The detector will only respond to light modulated at the correct frequency (usually around 40KHz). Maybe use the tone() function to modulate the IR led.
how wide is the drop point into the bag. 2", 4", ... does the product travel down the conveyor one by one or random groups. if one by one the break beam counter would work. Or i simple door switch thats triggered when the product moves the door it counts. like if you run your fingers along the vertical banisters on balcony's.
Answering some questions, there is no "drop point" . The snacks are molded by a machine then they are placed in trays, by hand, and go to the a fast freezer. After 30 minutes they are frozen and we take the trays out the freezer and pack it by hand.
So I will make a machine where the snacks are dropped on top of it and the machine releases 50 at a time in a bag below it then the employee seal the bag and place in the "cold room".
easy. make a slanted table out of stainless steel with sidewalls and one side having a slanted opening only big enough for one piece. So i assume the pieces are frozen. A frozen object slides very easy on Stainless Steel.
The employee will dump a tray of the frozen snacks on the table and they will gravity fall into the slanted opening.
at that opening have a break beam senor and a door that closes. Put a small buzzer or leds to indicate that 50 have dropped. I also assume that they are hand bagged. Set up a bag mount so the employee can grab the full bag and replace it with a new bag then hit a switch to reset the counter and open the door. After 50 drop the door will close and no more can fall until reset.
Mechanically could be done with Stainless Steel door on an actuator or a servo. just needs to open just enough to allow one unit at a time then close when done. The code for that would be relatively simple also/
codlink:
Production lines use weight to count. They dump a certain amount and weigh it, if it's correct, it proceeds down the line.
+1. Think about how light beams, conveyors, dumpers and all that stuff could slow down your flow. There is reliability and maintenance to consider too. What happens when your fancy light beam counter breaks because the sensor is full of salgado crumbs? The line stops.
I agree that weight to count is the faster way, but the problem is that machine that produces the salgados is not accurate with the weight and the product is sold by 50 un.
We could change to sales based on weight, but no salgado manufacturer does it and people are not used to buy these salgados by weight. Also customers here in Brazil are INCREDIBLY picky... if we sell 500 salgados and deliver 499 they will come back furious... Brazilians love to feel scammed and make a big scene out of it... play the victim.
