Index Mechanism, Late - IBM Selectric Reference Manual

1.
2.
INDEX MECHANISM - (LATE)
All operational control adjustments must be correct be-
fore any attempt is made to adjust i·he index mechanism.
Multiplying Lever Stop - (Fig. 216) - Adjust the mul-
tiplying lever stop front or rear to produce .360
II
to
.375
11
(approximately 3/8
11
)
motion to the index link
when the carrier return/index cam is operated to its
high point (platen removed).
. 360
11
to .375
11
FIGURE 216. Multiplying Lever Stop (Late Style)
NOTE: This adjustment may be
me~asured
with the
Hooverometer and a feeler gauge. The handle of the
Hooverometer is .375 11 wide.
Figure 217 illustrates the first level multiplying lever
stop used on the new style index mechanism. This stop
should be adjusted both horizontall:f and vertically.
The stop is adjusted vertically so that the multiplying
lever wi /I operate above and below a horizontal posi-
tion by an equal amount. The horizontal and vertical
adjustments of the stop must be made alternately unti I
both are correct.
. 360 11 to .375"
FIGURE 217. Multiplying Lever Stop (Early Level)
3. Index Link - Use the following procedure to adjust the
index link:
a. As a preliminary step, loosen the platen overthrow
stop and move it to the front (Fig. 218).
b. With the platen installed, hold the detent roller
~:c;engaged
from the platen ratchet with a spring
hook while an index operation is manually cycled.
At the completion of the operaf'ion allow the detent
roller to re-enter the platen ratchet. If the index
Platen Overthrow
Stop Moved To The
(Index Operation Manually
Operated Through)
Front
4 •
Detent Held Disengaged
Index link
FIGURE 218. Index Link Adjustment
link is properly adjusted the detent roller will seat
between two ratchet teeth without causing any ro-
tational motion to the platen. Adjust the link to
obtain this condition.
Platen Overthrow Stop - With the index cam rotated to
its high point, ad just the platen overthrow stop to clear
the index pawl by .005" to .020" (Fig. 219).
Index Link
FIGURE 219. Platen Overthrow Stop Index Selector Cam
5.
Index Selection Cam
a. With the index cam latched at rest and the se-
lection lever in the double line space position,
adjust the selecti on cam front to rear so that the
index pawl clears the platen ratchet by .015 11 to
.050 11 (Fig. 220) •
FIGURE 220. Index Selection Cam Adjustment
b. Adjust the selection cam up or down so that the
index pawl is centered on the cam surface with the
selection lever in the single line space position
(Fig. 221).
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