mechanical
The mechanical design for our coin sorter was focused around a 7/8 in. diameter hollow aluminum shaft
which ran vertically through the center of our sorter. One end of this shaft was attached to our motor,
and the other contacted the surface of the base plate.
At the top edge of the coin sorter is located a coin-feeder which allows a user to input his/her change.
This change then enters the top coin bin, of which there are four.
These bins are positioned along the height of the sorter and correspond to quarters, nickels, pennies,
and dimes (from top to bottom). Also attached to the shaft were three threaded rods at heights which
were slightly above the bottom surface of each of the top three plastic bins. Small sections of windshield
wiper blades were affixed to the bottom of the threaded rods, which had a flat milled along one edge for this
purpose of attachment.
 
The top three plastic bins had holes machined into them. The top-most bin had holes which were slightly smaller
than the diameter of a quarter, the one beneath it had holes slightly smaller than the diameter of a nickel, and
the third had holes just smaller than the diameter of a penny. The proper coins would be allowed to pass through
these holes and would land on a funnel positioned at an angle which would catch the coins and pass them through a
transparent tube to the next coin bin.
The basic operation of the sorter is as follows: first, the machine would be turned on, powering the motor which
in turn drove the center shaft. Change would be input by the user and would enter the top bin. The coins would be
swept around by the wipers and fall through the coin holes, passing from layer to layer until they were entirely separated
into the categories of quarters, nickels, pennies, and dimes.
The entire design was supported by right angle aluminum stock mounted to square bases on the top (on which the motor, handyboard,
and keypad were mounted) and bottom. The plastic bins were held up by long screws which were threaded into the angle stock; the
bins were also held in place by wire which affixed them to the screws. The funnels which moved coins from bin to bin were also
attached by wire. The position of these was controlled by wire on two sides of the funnel and a notch cut into the next bin in which
the funnels' plastic tubing would sit, thus securing the funnels' positions.
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