Hey, I want to understand how an SMD parts counting machine work. What sensor does it use to detect the parts?

Moderator's note:
For background, this is closely related to another thread:

https://forum.allaboutcircuits.com/...pick-and-place-operation.146724/#post-1248875

 

Hey, I want to understand how an SMD parts counting machine work. What sensor does it use to detect the parts?

I don't know how commercial machines work. If I were doing it, I would use a photo-interrupter for my first try. Many (all?) tapes that hold SMD parts have a hole or clear tape to let light through when the part has been removed.

If that is not an option then I would count the holes in the tape used for the sprocket feed. The disadvantage of this is that different parts have a different number of holes per part.

Hopefully there are others here that have actual knowledge of the operation of production machines.

 

First hit with Bing...
https://www.manncorp.com/component-inventory-management/component-counters-2000pc.html