IBM Selectric Maintenance Manual page 56

Tab Rack Plate
FIGURE 99. Tab Rack Plate
NOTE: The following relationships are affected by the
position of the escapement bracket - tab lever trigger
to tab torque bar, tab lever pawl to tab rack, tab lever
to escapement and backspace pawls, tab lever trigger
to tab overthrow stop, escapement and backspace pawls
to escapement torque bar, escapement torque bar to pawl
pivot stud, and escapement torque bar to tab latch.
Each of these relationships must be checked and read-
justed if necessary after any adjustment of the escape-
ment bracket.
2. Escapement Torque Bar Stop
a.
b.
Late - rhe torque bar stop located at the right end
of the torque bar shou I d be ad justed for a rest posi-
tion clearance of
.008"
to
.010"
between the tor-
que bar and the lug on the escapement pawl (Fig.
100).
FIGURE
-100.
Torque Bar Stop
Early - Form the torque bar stop located at the left
end of the torque bar so that a clearance of
.002"
to
.006"
exists between the torque bar and the lug
on the escapement pawl (Fig.
101).
The escapement cam used with the new style es-
capement mechanism provi des greater available
trave I for a II escapement parts; therefore more
clearance is permissible and desirable between the
torque bar and the escapement pawl lug.
CAUTION: Make certain that the escapement
trigger does not prevent the escapement torque bar
from resting against the stop when making the torque
bar stop adjustment. Also, check the pawl mount-
ing stud and, on long carriage machines, the torque·
bar back stop. Neither one of these shou Id be
touching the torque bar when the stop adjustment is
being made.
-...... _ _ -..,.. Form Stop To Obtain Clearance
_-----Torque Bar
FIGURE 101. Torque Bar Stop
3. Pawl Mounting Stud - Rotate the pawl mounting stud so
that it clears the escapement torque bar by
.001"
at the
closest point along the writing line (Fig. 102) Keep
the high part of the eccentric toward the left so that the
force of the torque bar wi
II
tend to tighten the stud in-
stead of loosen it.
4.
. Torque Bar
~!----.~----~~
Stud
FIGURE 102. Pawl Mounting Stud Adjustment
Tor1ue Bar Back Stop - Adjust the back stop forward or
bac on its mounting stud so that there is a .001" to
.005" clearance with the torque bar (Fig. 103).
FIGURE 103. Torque Bar Backstop
5.
Pivot Pin Eccentric (found on early level machines only)
The eccentric collar should be adjusted with the high
point up so that it just touches the operational latch
bracket (Fig.
104).
This prevents the pivot pin from
bowing during a print escapement operation. The
eccentric should also be adjusted laterally on the
pivot pin so that the end play of t.he pivot pin wi
II
be .002" to .005".
2-32.1