IBM Selectric Reference Manual page 39

6.
This clearance insures positive unlatching of the
upper case armature.
b. Up or Down - UC armature (energized) clears the
LC armature (at rest) by .003
11
to .006 11 (Fig. 78).
Armature Energized
Armature At Rest
L.C. Magnet
• 003 11 to .006"
FIGURE 78. LC Magnet Assembl'Y (Up or Down)
When the upper case armature ns picked the lower
case armature must be able to snap forward and
latch the upper case armature. If the clearance
is excessive the upper case armature may move far
enough to allow a shift to take place. When this
happens the printer wi II be in lower case while
th~
magnet assembly is latched in upper case.
Magnet Assembly Mounting Bracket (Early)
a. 11 Inch Machine (Fig. 79) - Position the magnet
assembly mounting plate (front to rear) sothat the
UC armature (at rest) clears the release arm pin by
.002" to .008".
Shift Release Arm
.002" to .008" Clearance
Rele~ase
Arm Pin
U . C. Armature At Rest
';1"'--+-+-__
Magnet Mounting Plate
FI GURE 79. Magnet Assembly Mounting Bracket
7.
2-21
b. 15 Inch Machine And All Late Style Shift (Fig. 80)
- Position the magnet assembly mounting plate (UC
armature energized) so that the release arm clears
the shift ratchet lug by .005
11
to .015
11
•
Shift Release Arm
Mtg .
FIGURE 80. Magnet Assembly Mounting Bracket
UCArmature Backstop, 151nch Machine (Earl) Fig. 81) -
Position (armature at rest) so that the U a.rmature clears
the release arm roller by .002
11
to .008
11
•
The clearance between the UC armature and shift re-
lease arm allows the armature to be in motion prior to
picking up the load of the release arm. With no clear-
ance the armature may fail to pick.
.002" to .008"
I
U.C. Armature
(At Rest)
Shift Release Arm
FIGURE 81. U.C. Armature Backstop