IBM Selectric Manual

8.
Just Bottoms
FTGURE 25a. Shift Interlock
b. 721 Only - With the shift interlock on the high
point of the cam, form the interlock so that the
tip just bottoms between two teeth on the ratchet
{Fig. 25b}.
Form Here
Cam
On High Point
FIGURE 25b. Shift Interlock
Shift Interlock Cam - With the cycle clutch latched at
rest and the backlash of the cycle shaft and fi Iter shaft
removed in the operating direction, advance the cam
unti
I a clearance of .040" to .060" exist between the
tip of the interlock and the top of a tooth on the shift
clutch ratchet {Fig. 26}.
.040" To .060"
FIGURE 26. Shift Interlock Cam
9. Character Interrupter - The character interrupter bail
plate is adjusted in its elongated slot to satisfy 2 condi-
tions.
a. With the shift cam detented in lower case and the
cycle clutch latch I ink released forward, the char-
acter interrupter pawl should clear the bottom of
the link by .015
11
to .020
11
{Fig. 27a}.
b. With the shift cam undetented and the cycle clutch
latched to the rear, the character interrupter pawl
should
clear the front of the cycle clutch latch
link by .015
11
to .020
11
{Fig. 27b}.
Cycle Clutch link
Released Forward
.015" to .020"
.030'
A. VERTICAL CLEARANCE
Cycle Clutch Link
Held
To The
Rear
By The
Keeper
L .015" to .020"
B. HORIZONTAL CLEARANCE
FIGURE 27. Character Interrupter Adjustments
cye U: CLUTC H
1.
2.
Cycle Shaft - Shim the cycle shaft to obtain. 001" to
.003" end play of the shaft. The shims are placed be-
tween the left hand bearing and the check ratchet. The
shims
are avai lable in various thicknesses and are coded
by shape as described in the Part:. Catalog.
CAUTION: The sl ight end play of the shaft insures that
it will rotate freely. Excessive play could allow 0 coil
ofthe cycle clutch spring to wedge between the two hub
members
ofthe clutch causing a machine lock-up. (End
play can most easily be measured with the spring clutch
removed .)
NOTE: With the end play removed to the right, maintain
.002
11
clearance between the cycle shaft gear and the
left hand bearing.
Cycle Clutch Latch Bracket - Adjust the bracket ver-
tically so that the steps of the cycle clutch sleeve are
horizontal when the sleeve is stopped by the latch
(Fig. 28).

IBM Selectric Specifications

General

Type	Electric typewriter
Introduced	1961
Keyboard Layout	QWERTY
Carriage Return	Electric
Manufacturer	IBM
Printing Technology	Typeball (golf ball)
Power Source	AC Power
Power Supply	120V AC