Teletype 28 Disassembly And Reassembly

TELETYPE CORPORATION
Skokie, Illinois, U.S.A.
SECTION 573-115- 702TC
Issue 3, September, 1964
1.
2.
28 TYPING UNIT
DISASSEMBLY AND REASSEMBLY
CONTENTS
PAGE
GENERAL . . . . . . . . . . . . . . . . . .
1
DISASSEMBLY AND REASSEMBLY ..
2
TYPE BOX . . . . . . . .
2
PRINTING CARRIAGE
2
TYPE BOX CARRIAGE . . . . . . . . .
2
FRONT PLATE . . . . . . . . . . . . .
2
STUNT BOX.. . . . . . . . . . . . . ... 3
STUNT BOX SWITCH . . . . . . . . . .
FUNCTION BAR . . . . . . . . . . . . . .
FUNCTION PAWL ... . ... .. ... .
FUNCTION LEVER . . . . . . . . . .. .
FUNCTION LEVER SPRING
PLATE . . . . . . . . . . . . . . . . . . . . .
CODE BARS.
MAIN SHAFT
UPPER DRAW WIRE ROPE . . . . . .
LOWER DRAW WIRE ROPE . . . . . .
PLATEN (FRICTION FEED) . . . . . .
3
4
4
4
4
4
5
5
6
6
PLATEN (SPROCKET FEED) . , . . . 6
SELECTOR CAM-CLUTCH . . . . . . .
7
SELECTOR MECHANISM . . . . . . . .
7
CODE BAR POSITIONING
MECHANISM . . . . . . . . . . . . . . .. .
7
RANGE FINDER ASSEMBLY ....
7
SELECTOR MAGNET ASSEMBLY
7
1. GENERAL
1.01 This section is issued to describe the
disassembly and reassembly procedures
for the 28 typing unit. Disassembly covers a
procedure for removing the principal sub-
assemblies which make up the unit.
1. 02 Reference should be made to the ex-
ploded views found in the appropriate
parts literature for an illustration of the mech-
anism to be disassembled, for location and
visual identification of parts, and detailed dis-
assembly and reassembly features.
1. 03 Disassembly should be confined to sub-
assemblies, which can, in some cases,
be removed without disturbing adjustments .
When reassembling the sub-assemblies, be sure
to check all associated adjustments, clearances,
and spring tensions.
1. 04 If a part that is mounted on shims is re-
moved, the number of shims used at each
of its mounting screws should be noted so that
the same shim pile-up can be replaced when the
part is remounted.
1.05 Retaining rings are made of spring steel
and have a tendency to release suddenly
when attempting to remove them. Loss of these
retainers can be minimized as follows: Hold
the retainer with the left hand to prevent it from
rotating. Place the blade of a suitable screw-
driver in one of the slots of the retainer. Ro-
tate the screwdriver in a direction to increase
the diameter of the retainer for removal.
1.06 Avoid loss of springs in disassembly by
holding one spring loop with the left hand
while gently removing the opposite loop with a
spring hook. Do not stretch or distort springs
when removing them.
1. 07 With cabinet lid raised or enclosure
cover removed, loosen and remove the
four screws that secure the typing unit to its
base. Disconnect the cable plug connector from
the side frame. Lift the typing unit off.
©
1953 and 1961 by Teletype Corporation in the United States. Copyright in all
countries participating in the International Convention and Pan American Con-
ventions. All rights reserved including rights of translation into all languages.
Printed in U.S. A.
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