7.Service
2.DC electric motor: The direct current (DC) motor provides the drive for the metering roll and is located on the front left hand side of standard model dryers. The output shaft of the motor is connected directly to the gear box assembly. (See Figure 7F.)
The DC motor requires no operational adjustment as it is completely controlled from the control box.
3.Speed reducer gear box: The direct drive gear box provides the required speed reduction,
and transmits power to the metering rolls through a drive chain arrangement. The gear box does not require adjustment. The drive chain should also be periodically lubricated and tensioned
as necessary. (See Figure 7F.)
4.Unload auger time delay: The delay controls the bottom auger system and causes the unload auger (and any connected auxiliary unloading conveyors) to continue operating for the programmed amount of time, even after the metering rolls stop. (See Figure 7F.)
This feature permits the
How to Determine a Metering Roll Problem
Figure 7G Metering Roll Drive
To determine if the metering problem is from blockage, perform the following test with the power OFF. Remove the drive chain by loosening the motor mounting bolts. Refer to Figure 7G, and place a pipe wrench on the hub of the roller chain sprocket, on the left hand metering roll at the drive end of the dryer. Apply up to 100 ft. lbs. of force, and try to rotate the roll towards the inside of the dryer. If the metering roll turns, then repeat for right hand side and it can be assumed that no blockage exists, and the problem is from some other cause. Check for a break in the power train, chain, drive key, pin, etc.
Keep hands away from sprocket teeth to avoid injury from chain backlash, as a result of torsion build up in the system caused by the jam.
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