Removing, Inspecting And Installing The Return Feed Assembly - Bayer HealthCare Clinitek Atlas Service Manual

9-4

Removing, Inspecting and Installing the Return Feed Assembly

9-4-1
To remove, inspect and reinstall the Return Feed Assembly, see Figure 9-3), do the following:
NOTE: Replace this entire assembly if repair is not feasible.
1. Turn off Rack Sample Handler instrument. Remove the Front Cover (item 5 on Figure 9-1) by removing
two small philips (or cross) screws (item 6) and two M3 x 12 metric allen screws (item 7).
2. Unplug cables CN203 (Motor) and CN123 (ORG4 Sensor) by pressing on their white plastic tabs to
release the connector plugs.
3. Remove the two vertical M4 x 12 metric allen screws (see arrow pointing to two vertical screws, item 20
on Figure 9-3) that hold the Return Feed Assembly to the instrument. Do NOT remove the two
horizontal screws marked item 20 on Figure 9-3! Lift the Return Feed unit to the left and up, out of the
instrument.
4. Once the unit is out of the instrument, inspect the two steel shafts (items 10 and 11) for cleanliness. Clean
both shafts with an alcohol wipe and place a thin layer of light machine oil over the entire surface of each
shaft. Rotate the Winding Drum (item 14) back and forth to move the Slide Block (43) one complete cycle
to evenly distribute the new lubrication. DO NOT over-lubricate the shafts!
5. Inspect the steel wire (item 22) for any frayed or damaged portions. Wire tension should permit deflection
of approximately one inch (25mm) from the center of this unit. Also inspect wire nuts (item 23) at end of
unit to verify hardware is all securely attached and compression springs (21) are not damaged.
6. Inspect the Winding Drum (14) set screws. Set screw at flat portion of the motor shaft must be below the
surface of the drum by approximately 3mm. Set screw at round portion of the motor shaft must be below
the surface of the drum by approximately 2mm.
If either set screw is loose, prepare screw threads with Loctite 425 Assure Sealant (or an equivalent metal
adhesive) and tighten screw until it is the proper distance below the surface of the drum.
7. Inspect the white teflon Lever (item 34) to verify it springs back promptly when pressed down. Also verify
attached tension spring (item 25) is properly installed and not stretched out or otherwise damaged.
Note the teflon lever does not require any lubrication and must be kept clean to operate properly. If
necessary, remove lever by loosening a screw and nut (items 32 and 36). Place a gap of at least 0.13mm
(0.005 inch) between the Lever and Catch Block (item 35) and tighten the screw and nut around this gap.
9-5