Laser Counter WANTED ! for stacked glass sheets 4

[youngd61]

Dear All,
We got problems when receiving packages of glass sheet especially thin glass 1.5 - 2.0 mm with content abt 200 -250 pcs/pack depend on sizes, we handle this job around 200-300 packages perday. The problem is there are so many wasting time to count the glass manually and always generate human errors.

ARE THERE ANY HANDY COUNTERS AVAILABLE to solve the problems? ( maybe Laser censored ??)

Condition :
1. The interleave between glass could be Papered or Powdered
2. Glass thickness in one pack may vary from 1.4 - 1.5 or 1.9 - 2.1 mm

Thank You

 

[dbaird]

Does the interleave between glass give some separation? Keyence (

http://www.keyence.com)

offers laser sensors with ultra small beam of 2 Mil that could give edge detection and if there is separation between glass you could index package through the laser and count the pulses it gives back into a PLC and/or counter for totalization.
David Baird
mrbaird@hotmail.com

Sr Controls Engineer

EET degree.

Journeyman Electrician.

 

[nbucska]

David:

The paper may have to be cut/burned off if it overhangs
the edge.

What about removing it with a rotating wire-brush ?
<nbucska@pcperipherals.com>

 

[IRstuff]

Are the sheets within the stack of uniform thickness w.r.t. each other?

TTFN

 

[IRstuff]

Sorry, mis-read condition 2:

Nothing completely off the shelf comes to mind, but here's a possibility:

Assuming you need and exact count:

Take the stack and tilt it and riffle it by allowing it to even up at the tilt. This gives you a stair-step profile, which you can run a profilometer across and use software to count the steps. If the interleaves underlap the glass, you could do this without the riffle step, since the profilometer would detect the gaps between the sheets.

TTFN

 

[IRstuff]

One other thought would be to use a vision system and a linear positioning mechanism that moves a camera along the stack and counts the sheets. Depending on the variance of the thicknesses and the accuracy of the positioning system, you could probably count twenty or so at a time. This is somewhat limited by how much contrast the gaps have.

TTFN

 

[youngd61]

Thank You,
dbaird : I'm in contact now with Keyence Singapore to find any solutions available.
IRstuff : 1. Tilting a stack of glass sheets are not allowed because could damage (or scratch) the near edge of them, also its too heavy +/- 1 ton each pack. But I will try to find some reff about profilemeter (thanks).
2. Vision system with camera seems too shopisticated and impractical for handy operations.

Best Regards.

 

[cbarn24050]

Hi, are the edges of the glass sheets exposed?

 

[youngd61]

yes, among the all of packaging 70% glass edges are exposed .

Regards

 

[cbarn24050]

Hi, in that case its easy. All you need is a thin metal strip, you run the strip up the stack each time it crosses the gap between the sheets there is a little click. A trasducer on the strip picks up the click and sends it to a counter. Of course it's much easier to get the machine that builds the stacks to count them.