NCR 7156, Service Manual

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7156 Service Guide Chapter 13: Drive Plate Assembly
September 1998 121
5. Pull back on the whole drive plate assembly to pull it off the top of the cantilever.
6. Pull up on the whole drive assembly to remove the bottom of the drive plate assembly
from the cantilever.
Disassembling the Drive Plate Assembly
The orientation for disassembling the drive plate assembly is upside down with the
carriage drive motor on the right.
1. Clip the tie-wrap that harnesses the interrupt sensor cable to the drive plate assembly
(top, right corner).
2. Remove the interrupt sensor assembly from the drive plate assembly mounting plate.
Note: The interrupt sensor assembly consists of the following non-serviceable parts: opto-
electronic coupler, sensor bracket, snap rivet (pin & housing).
a. Push in on the tip of the snap rivet pin.
b. Push the pin head through its housing.
c. Slide the sensor assembly off the carriage drive mounting plate.
3. Remove the timing gear and home flag from the carriage drive mounting plate.
a. Remove the e-ring on top of the timing gear.
b. Lift the timing wheel off the home flag.
c. Remove the home flag and torsion spring.
4. Remove the drive assembly pulley gear from the right side of the mounting plate (you
may need to remove the grommet to get to the pulley gear).
a. Remove the e-ring.
b. Remove the pulley flange.
c. Remove drive assembly pulley gear and bearing (if you left the grommet on, you
may need to pull back on the grommet to remove the gear).
5. Remove the grommet above the spring tensioner assembly on the left side of the drive
plate assembly.
6. Remove the spring tensioner assembly from the drive plate assembly.
Caution: This requires force. Take care that the spring doesn’t pop off and cause injury or
become lost.
a. Push tensioner to the left until it lines up with the slots in the mounting plate and
pops up.
b. Remove the compression spring from the tensioner.