Items used to determine the belt drive layout.
Marking screw holes for the Lazy Susan bearing.
Finding the center of the camera cylinder.
Placement of the driver cog and camera cylinder.
Final layout of the PanoramaScanCam™ belt drive.
| The belt drive layout for the PanoramaScanCam™ is modeled to determine where the cogs, pulley, and camera cylinder should be to allow reuse of the original drive belt of the scanner. After the mechanical layout of the floor of the UMAX 2100U was draughted, it was printed out to act as a positioning guide. It took a couple of attempts to get a printout that was correctly scaled. The disks are cut from foam core board to represent the drive and idler cogs (15 millimeters), a pulley (40 millimeters), and the camera cylinder (3.5 inches). The Lazy Susan bearing is used as its own template for positioning screw holes and for locating the center point of the camera cylinder. Push pins are used to secure everything to a cork board. |
Items used to determine the belt drive layout. |
| The Lazy Susan bearing is first positioned to provide solid mounting points for the screw holes on the raised portions of the scanner floor. The opening of the bearing is offset to allow the ribbon cable to curl counter-clockwise up the camera cylinder to where it connects to the scanner board. A pencil is used to mark the screw holes on the drawing. |
Marking screw holes for the Lazy Susan bearing. |
| A pencil and straight edge are used to draw diagonal lines between the markings for the screw holes of the bearing. The screw holes are symmetrically placed on the bearing, so the intersection point of the two lines is the center of the camera cylinder. |
Finding the center of the camera cylinder. |
| The scanner floor drawing is secured to the cork board with push pins. Then the foam core disks representing the camera cylinder and the driver cog are placed that their proper locations. The center of driver cog is located at the crosshair on the upper left corner of the gray rectangle. The center of the camera cylinder is located at the intersection of the lines just drawn. Push pins are used to secure the disks. The scanner belt is laid down such that it surrounds both disks. |
Placement of the driver cog and camera cylinder. |
| The idler cog and tensioner assembly of the scanner are being reused, so it is necessary that the idler cog lie on the centerline drawn on the lefthand side of the drawing. With the disk representing the idler cog and the pulley placed with the belt, some shifting and tugging is performed until a suitable belt drive layout was achieved. Push pins are use to secure the idler cog and pulley. The belt is slightly taught, but not excessively so. Attempts to pull the belt too tight results it one or more of the push pins pulling out of the cork board. It should be noted that the position of the idler cog represents where it will be with the tensioner assembly pushing against the belt. Without the belt in place the spring on the tensioner assembly pushes the idler cog about 5 millimeters further down the centerline. After removing the push pins, the holes that are left can be measured and added to the drawing. |
Final layout of the PanoramaScanCam™ belt drive. |