|
Before construction of the PanoramaScanCam™, could proceed, it was
necessary disassemble the scanner to determine its layout and construction.
Exploiting or compensating for unique features of the scanner would determine
the degree of difficulty and success in converting it to the
PanoramaScanCam™. Below is a dissection of the UMAX 2100U used for my
project.
|
|
The UMAX 2100U with the lid raised. The lid pops off at the hinges easily.
The hinges are made of plastic and can break if the lid is twisted. There are
two Phillips head screws near the hinges on the top deck of the scanner. These
are also removed easily. The screws secure the top deck of the scanner to the
scanner body along with two molded brackets at the front of the scanner.
Lifting the rear of the top deck and pushing the deck forward releases it from
the scanner.
|
Scanner with lid open.
|
|
As with most scanners, the interior is mostly empty space. Of course, the
space is there to allow the scan head to move during the scan. The metal bar
guides the path of the scan head. The white ribbon cable carries data and
power between the scan head and the controller board (underneath the scan head
in this picture). Notice that the design of the scanner case has an integral
cable tray for the ribbon cable to lie in as the scan head moves over it. This
will be taken advantage of in the design of the PanoramaScanCam™.
|
Scanner with lid and top cover removed.
|
|
Moving the scan head forward reveals the controller board. The stepper motor
and gear assembly is also visible (top left). Notice that only a single guide
bar is used to direct the motion of the scan head. The opposite side of
the scan head is supported by and idler wheel.
The board on the scan head is the scanner board. It holds the CCD module
and some electronics used to drive it. The black "U" on the left
top of the scanner board is a optical switch. It is used to detect when the
scan head is at a positional reference point within the scanner. A plastic
"finger" inside of the scanner lid can interrupt the IR beam directed
from one side of the optical switch to the other. The interruption of the
beam signals the scanner that the scan head has reached the reference position.
|
The scan head and controller board.
|
|
This is a closer inspection of the controller board, scanner board, and
stepper motor. Note also the ferrite noise suppressor on the ribbon cable.
This is used to reduce AC noise reaching the electronics in the scan head. The
wires connected on the right side of the controller card supplies power to the
stepper motor. The wires on the center connector provide power and signal for
the control buttons on the front of the scanner.
|
Controller and scanner boards and stepper motor gear assembly.
|
|
Another view of the stepper motor and gear assembly. The scan head is moved
via a cog and belt assembly. The length of the belt is designed to support
scans up to 11.7 inches in length. For the PanoramaScanCam™, the linear
movement will be tranformed into rotation. Note that the diameter of the
driver cog, where the belt contacts, is 15 millimeters.
|
Close-up of the stepper motor gear assembly.
|
|
The other end of the scanner's interior reveals the idler cog for the drive
belt. The tension on the idler cog keeps the drive belt taught around the
drive cog on the gear assembly. The idler cog and tensioner assembly will
also be used in the PanoramaScanCam™. Like the driver cog, the diameter
of the idler cog, where the belt contacts, is 15 millimeters.
|
Idler cog and tensioner assembly.
|
© 2007 Mac A. Cody