Common Problems Encountered. Because the tolerance
is 170 for the wide-view and 150 for the
narrow view cameras (over half of the gray-scale), this
can allow the nozzle back disk to degrade to the point
that the separation value discussed above is less than
100, and the camera cannot process the part body and lead
definition. Most customers try to compensate for poor
back disks, by increasing the gain level for each camera.
This will only aggravate the problem, because by increasing
the camera gain level, it will shrink the pixel size of
the camera, causing more part body and lead definition
problems.
1. Some nozzle back disk manufacturers have problems keeping
a consistent level of brightness from one size to another.
The smaller diameter nozzles are sometimes bright enough;
however, the brightness decreases as the diameter increases.
As you have only one brightness tolerance and deviation
setting for all nozzle sizes, this can cause problems
on larger leaded components.
2. Poor condition of the camera lighting, black-light
bulbs can cause brightness level problems and image processing
problems.
3. Many customers do not understand how the gain and offset
levels work. If adjusted improperly they can cause image-processing
problems. The gain level is for brightening an image,
and the offset is for darkening an image. If you wish
to increase the brightness of an image, set the offset
to 0, and raise the gain level. If you wish to darken
the image, set the gain level to 0, and raise the offset
level.
By setting up your machine properly, including backlight
tolerances, deviation tolerances, gain and offset level
adjustments, and backlight bulb condition, you can reduce
image processing time, and processing errors.
Please refer to SMD3 Vision System Setup document for
proper setup of your machine. By following thes etup procedure,
it will allow you to discern poor back disks, and failing
backlight bulbs. Once the setup is performed your machine
will monitor nozzle back disk condition. Then it will
indicate when back disks need to be cleaned or replaced.
This is done without needing to change gain level settings
which can adversely affect image processing.
This document is for Fuji CP4-2 through CP643 series machines.
There are some differences due to firmware versions. The
CP7 series machines have a different baseline adjustment
procedure. |
If you have any questions, or encounter any problems,
please contact me at:
Mike Forseen
Senior Process Engineer
mike@smtresearch.com
Phone (319) 367-5000
Cell (319) 601-1285
Fax (319) 367-5155 |
|
