mawa wrote:
This little board has been made without any extra cost by my PCB manufacturer
Unfortunately any board that fits into the nozzle shaft would have a maximum dimension of less than 1/3rd of the board you show.
I mean we're talking really, really, really tiny here.
I'll take exact measurements as soon as this run finishes (it's placing right now... bad time to disassemble the pickup head!).
Edit: okay, I put the digital calipers on it.
The majority of the shaft is a 5mm bore; if the contact is
smaller than this then it needs to have some extra mechanism to prevent it from being sucked up the tube by the vacuum. So most likely it
should measure more than 5.0mm in at least one direction.
The bottom portion of the holder is a cylindrical chamber 6.98mm (say 7) in diameter. The contact
MUST be no larger than this in any X-Y plane direction. That's what I mean when I say tiny. The
largest it could possibly be is a 7mm-diameter disc.
The chamber is approximately 10.3mm tall. I can't quite get the calipers in there, so this number came from measuring the nozzle head and some subtraction; not as exact as the others.
The part of the nozzle-tip that pushes up to make electrical contact is a tube, 3.19mm outside diameter and 2.06mm inside diameter. So the contact plate should have a 2mm drill in the center (to let air through) surrounded by a 0.565mm-wide ring of copper. The part that pushes up is contained in a 3.73mm-diameter housing which is supposed to be grounded, so that can't contact the copper ring on the contact plate -- this determines the maximum opening in the solder mask.
Here's a first sketch, and the gerbers, hastily thrown together just to see how much of a fit OSHPark throws over it... for five bucks shipped with ENIG gold finish... hey I can afford to be wrong here.
- juki_nozzle_plate_10.png (111.02 KiB) Viewed 22566 times
Well, their automated system accepted the order. Let's see how it turns out.
- oshpark-paid.png (79.59 KiB) Viewed 22566 times