Escapement Mechanism - IBM Selectric Reference Manual

Yoke
L---_rL--
Mtg. Screw
(
~~----~---
Remove
FIGURE 142.16 Pivot Plate
b. Check to see that the residual is flush against the
yoke (Fig. 142.17).
~--Residual
't:::-.J.\v~~-"'::::Mtg. Screw
Armature
FIGURE 142.17 Residual
c.
Position the backstop for .030 11 to .035 11 between
the armature and yoke with the magnet de-energized
(Fig. 142.18).
FIGURE 142.18 Dual Velocity Magnet Assembly
15. Dual Velocity Magnet Assembly (Installed) - With the
armature held in a de-energized position, adjust the
magnet front to rear to obtain .010 11 to .015 11 clearance
between the armature and the low velocity latch (Fig.
142.18) •
1.
ESCAPEMENT MECHANISM
Escapement Bracket (Printers With Tab)
a. With the carrier to the left, ad just the escapement
bracket front to rear so that .001"'to .002" exists
between the raised area of the escapement bracket
and the tab torque bar. The rear surface of the es-
capement bracket should be kept parallel with the
tab torque bar (Fig. 143). Early printers which do
not have a raised area should be adjusted for .0111'
to .017 11 between the escapement bracket and tab
torque bar • To aid in ad justment on 767, remove
or loosen the tab torque bar support bracket.
.00111 to .00211
o
o
~~--------~
0
o
Early Printers
.01111 To .017 11
o
Escapement Bracket
Positioned To Obtain
Clearance
Check Entire Length Of Writing Line
For Possible Warped Torque Bar
FIGURE 143. Escapement Bracket (With Tab)
b. With the carrier to the right, form the extension on
the tab rack plate so that .001 11 to .002 11 exists be-
tween the raised area of the escapement bracket
and the tab torque bar. This is the extension which
supports the tab torque bar on the right side (Fig.
144). Note: This part is case hardened on early ma-
chirres. Use caution when forming. Adjustment a.
shou Id be rechecked if this extension is formed.
FIGURE 144. 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
pi vot stud, and escapement torque bar to tab latch.
Each of these relationships must be checked and re-
adjusted ifnecessaryafter any adjustment of the escape-
ment bracket.
Escapement Bracket (Printers Without Tab) - Position the
escapement bracket so that a 5" screwdriver blade spans
the distance between the rocker shaft set screws and es-
capement bracket as shown in Fig. 145. Be sure and
check both sides.
Carrier
Casting
FIGURE 145.
Spans Distance From
Escapement Bracket
To Front Si de of
Screw Hole.
Escapement Bracket (Without Tab)
2-51