IBM Selectric Maintenance Manual page 33

If the bracket were adjusted too low, the steps woll Id be
at an angle to the line of motion of the cycle clutch
latch. The latch would have difficulty in moving for-
ward to release the clutch sleeve, and a slow, hesitant
operation would result.
With the bracket too high, the force of stopping the
cycle shaft through the cycle clutch sleeve would tend
to cam the latch forward. A repeat cyc Ie operati on
could result.
When properly adjusted the top of the latch pivot pin is
1.546" below the top of the print shaft. This distance
can be measured wi th the use of the Hooverometer. Wi th
the head of the Hooverometer set at the
#3
scribe line,
the head should rest on top of the print shaft with tl-e
handle touching the latch pivot pin (Fig. 41). Be sure
the Hooverometer handle is vertical. It will be vertical
if the base of the handle is centered over the latch pivot
pin.
NOTE: Changing the height of the cycle clutch latch
necessitates a readjustment of the cycle clutch collar,
cycle clutch stop, and the cycle clutch latch restoring
mechanism.
CA.UTION: The latch bracket must not become cocked
so that only a corner of the latch plate is stopping the
sleeve. Excessive wear could result. The cycle clutch
sleeve could also be tilted by the latch causing it to
bear against the cycle clutch pulley hub creating a
noisy operation.
3. Cycle Clutch Spring and Collar Adjustments (Early)
a.,
Lateral position of the spring - Loosen the collar
and position the spring left or right on its hubs so
that the right hand end of the spring wi II clear the
face of the cycle clutch pulley by .004" to .012"
(F.ig. 42).
NOTE: This adjustment insures that a maximum
number of coils of the spring clutch wi II grip the
driving hub during a cycle operation. Any slip-
page between the driving hub and the spring clutch
could decrease the typehead velocity during a
print operation resulting in intermittent light im-
pression. A lack of clearance between the right end
of the spring clutch and the face of the cycle clutch
Sleeve
Collar Adjustment
Pulley
Cycle Clutch Spring Sleeve End Play
FIGURE 42. Lateral Position of the Cycle
Clutch Spring and Collar
pulley would create a bind causing the spring clutch
to place a heavy torque on the cycle clutch sleeve.
This excessive torque on the sleeve results in a
sluggish operation because the cycle clutch latch
trip lever has difficulty tripping the latch off the
sleeve.
b. Lateral position of the collar - position the collar
left or right so that the sleeve will have .010" to
.015" end play.
NOTE: This adjustment insures that there will be
no binds between the right end of the sleeve and the
cycle clutch pulley. A bind will cause a sluggish
operation just as in the previous adjustment.
c. Radial position of the collar - (The position of the
collar directly controls the radial position of the
left hand end of the cycle clutch spring with respect
to the cycle shaft. It determines how much the
clutch spring wi II be expanded when the cycle
clutch is latched and the cycle shaft is in its
rest position). Adjust the collar so that when a zero
ti It, negative-five rotate character is hand cycled
the cycle clutch spring will begin to slip (expand)
when the cycle shaft is 1/16" to
3/32"
from its rest
position measured on the surface of check ratchet
(Fig. 43).
This adjustment is difficult to observe at the check
ratchet. A 1/16" to
3/32"
rotation of the cycle
shaft wi II cause the print shaft gear to turn approxi-
mate
y
one tooth. The adjustment can easi ly be
read by one of the foil owi ng methods.
Cycle Clutch
Check Ratchet
Note: The positive cams are
almost horizontal when the
1/16" To
3/32"
cycle cl utch is latched.
FIGURE 43. Radial Position of Cycle Clutch Collar
A. Pri nt Shaft Gear Method
1. Hand cycle a zero ti It, negative-five character
until the cycle clutch begins to slip.
2. Pencil mark the print shaft bearing in line with
a tooth on the gear.
3. Release the cycle clutch again by depressing
a selection magnet armature.
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