IBM Selectric - Page 70

2. Escapement Torque Bar Stop
a. Late - The torque bar stop located at the right
end of the torque bar should be adjusted for a rest
position
clearance of .008" to .010" between the
torque bar and the lug on the escapement pawl (Fig.
146) .
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3.
b.
Torque Bar Stop
FIGURE
146. Torque Bar Stop (Late)
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 I ug on the escapement pawl (Fig. 147).
........... _--Form Stop To Obtain Clearance
... ______ Torque Bar
FIGURE 147. Torque Bar Stop (Early)
The
escapement cam used with the new style escape-
ment mechanism provides greater available travel
for all escapement parts; therefore more clearance
is permissible and desirable between the torque bar
and the escapement pawl lug.
CAUTION: Make certain that the escapement trig-
ger does not prevent the escapement torque bar from
resting against the stop when making the torque bar
stop adjustment. Also, check the pawl mounting
stud
and, on long carriage machines, the torque
bar back stop. Neither one of these should be
touching the torque bar when the stop ad justment is
being made.
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. 148). Keep the
high part 'of the eccentric toward the left so that the
force of the torque bar wi II tend to ti ghten the stud in-
stead of loosen it.
4.
5 .
!
. 001" Torque Bar
t
t C \
1--(0;)== Pawl Mounting Stud
FIGURE 148. Pawl Mounting Stud Adjustment
Torque Bar Back
Stop (long carriages only) - Adjust the
back stop forward or back on its mounting stud so that
there is a .001" to .005" clearance with the torque bar
(Fig. 149).
NOTE: Position carrier so back stop is opposite pawl
mounting stud.
/- -,
I)f'\-.. .......
( ~ I
\ f J
" /'
--
Late (form)
.00 I" to /..- ~"''' \
.~5~ jl0
I~
" /
"- -
FIGURE 149.
Torque Bar Backstop
For 767
adjust escapement torque bar backstops front to
rear for .001" motion of torque bar between pawl mount-
ing stud and backstops when carrier is positioned at each
backstop. Position stops vertica Ily to contact torque bar
no higher than the center of lower radius of torque bar.
Pivot Pin Eccentric (found on early level machines only)
The eccentric collar should be ad justed with the high
point up so that it just touches the operational latch
bracket (Fig. 150). This prevents the pivot pin from
bowing
during a print escapement operat'ion. On long
carriage machines the eccentric should also be adjusted
I atera II y on the pi vot pi n so that the end pi ay of the
pivot pin will be .002" to .005".
Carrier Return
Latch
Arm
Latch Bracket Assembly
6.
Eccentric Should
....... r.a--- Be Up And Touch-
ing Latch Bracket
FIGURE 150. Pivot Pin Eccentric
(Early Level Machines Only)
NOTE: The eccentric may require a readjustment if
the rest position of the pivot pin is changed during car-
rier return adjustments.
Escapement Cam - Adjust the cam by rotating it on the
fi Iter shaft so that the cam follower roller just reaches
the low point of the cam at the rest positi on (Fig. 151).
The cam is accessible from the top by inserting the
Bristol wrench between the carri er return and backspace
keylevers just in front of the margin rack.
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