Backspace Mechanism; Spacebar Mechanism - IBM Selectric I/O Reference Manual

MACHINE
1447
1052
1053
1062
BREAK
15 ± 10
15 ± 10
15 ± 10
15 ± 10
C-5
Nit
Figure 135. Timing Chart
MAKE
105 ±5
105 ±5
105
±Si
105 ± 5
I
NOTE: Trip the Tab Interposer, turn the operational shaft
unti
I
the cam just starts to turn. This is zero degrees.
SPACEBAR MECHANISM
1. All print escapement and.operational control adjustments
must be correct before attempti ng adjustments of the
spacebar.
2.
Spacebar Latch Lever Screw - Adjust the screw so that
.007
11 to .0lOli clearance exists between the escapement
trigger and the escapement torque bClr (Fig. 136A). Dis-
connect the escapement trip link before making this ad-
justment.
.007"
to
.010'~
- " \
I~\.;) \
Trigger
~~
Adjusting Screw
r--
FI GURE 136A. Spacebar latch Lever Screw
(Long Carriage)
The trigger upstop should be moved up out of the way
when making this adjustment. After completing the ad-
justment the upstop should be adjusted so that it clears
the trigger lever by .001" to .005" (Fig. 136B).
This adjustment insures that the trigger will properly re-
set over the lug on the escapement torque bar at the com-
pletion of each spacebar operation. It also insures that
there wi
II
be a maximum transfer of motion from the
spaCebOi
opeiotional latch
to
the trigger lever assemb!y,
thereby placing a sufficient amount of wear potential
into the system (which is felt as trigger overthrow).
?-L11
Trigger Upstop
/
.,/"
.005 11
FIGURE 136B. Trigger Upstop
BACKSPACE MECHANISM
1. Be sure the print escapement and operational control ad-
justments are correct before attempting backspace ad-
justments.
2.
Tab Lever Stop - The rest position of the tab lever is
controlled by a lug on the escapement bracket called
the tab lever stop (Fig. 137). The stop shou Id be formed
front or rear so that a clearance of .00111 to .003" exists
between the vertical lug on the tab lever and the back-
space pawl when the backspace pawl is bottomed in its
rack.
/ /
"
Tab Lever Stop
,....._.,.0-._.001" to .003"
FIGURE 137. Tob Lever Stop Adjustment
The tab lever stop may be formed by inserting the T-
bender from the upper right si de. It
wi!!
be necessary to
force the tab torque bar to the rear in order to insert the
T -bender.