IBM Selectric Reference Manual

a. Vertically - to provide equal spring tension on all
armature springs.
b. Horizontally - so that all armatures are centered in
thee guide slots.
Armature
II!III~-- Pivot Plate
Yoke
I"""~-- Guide Plate
FIGURE 27. Pivot Plate
Stop~~:~~w~tgi::::t
~.
~
"\:J
3.
4.
-. :.:;
~-~--- ~
Guide Plate Screw
Armature Stop Stop Screw
FIGURE 28. Armature Stop
Armature Stop - With the armature manually attracted,
adjust for a clearance of .004
11
to .008" between .the
armatures and yokes (Fig. 29 - see Fig. 28 'for assembly
end view). Measure clearances at the outside armatures
(T2 & R5).
F
I GU RE 29. Armature Stop
Armature Guide - Position horizontally so that the arm";'
atures are centered in the guide slots (Ref. Fig. 28).
2-8
5.
Back Stop (Fig. 30) - Position vertically (with armatures
at rest) for a clearance of .041" to .044" between the
armature stop and armatures. Measure clearance at the
outside armatures (T2 & R5).
Armature
'""-..,,~ ... __ Mtg. Screw
.04111
Armature Stop
6.
FIGURE 30. Armature Backstop
Pivot
Eccentrics (Fig. 31) - Adjust so that the cycle
clutch trip bail is parallel to the armatures. The follow-
i ng procedure may be used.
a. Disconnect the trip I ink (Fig. 35).
b. Apply slight pressure to the knock off extension
(Fig. 34) or trip link extension to hold the bail
in contact with the armatures.
c. Apply sl ight pressure to the T2 and R5 armatures
(Ref. Fig. 27). Both armatures should be touching
the trip bail. If not, adjust the pivot eccentrics
to satisfy this condition.
NOTE: The high point of the pivot eccentrics
must be toward the top (paper feed area) of the
machine.
d. After completing step c, while holding the trip
bail against the armatures, check the center arm-
atures to be sure they are touching the trip bail or
clear it by a maximum of .002
11
. Excessive clear-
ance can cause extra cycles.
NOTE: Item 6 is a preliminary adjustment. For final adjust-
ment, see note under Item 3 of cycle clutch trip mechanism.
Pivot Eccentrics
Knock-Off Extension N
Armature
7.
J ust Touches
Trip Bail
FI GURE 31. Pivot Eccentrics
Magnet Unit (Fig. 32) - Position under its two mounting
screws
for. 005
11
to .010" clearance between the pusher
tai Is and armature latching surfaces (armatures at rest).

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