Teletype 28 - Page 157

ISS 8, SECTION 573-118-700TC
4.02 Ribbon Feed Mechanism for Chadless Tape and Fully Perforated Tape (continued)
(A) RIBBON FEED DRIVE ARM SPRING
(C) RIBBON
RATCHET WHEEL SPRING WASHERS
Requirement
Requirement
With unit in stop position
Min 3 oz---Max 5 oz-------.
to pull spring to installed
With feed pawl and retaining pawl shifted
to opposite ratchet wheel
Min 1 oz---Max 2-1/2 oz--------.
to start wheel turning.
length.
RIBBON FEED PAWL
To Adjust
Remove retaining ring and bend spring
washer. Replace retaining ring.
Note: Make this adjustment for both ratchet
wheels.
RATCHET WHEEL
SPRING WASHER
RETAINING RINGS
RIBBON FEED DRIVE ARM SPRING
(B) RIBBON FEED PAWL DOWNSTOP ECCENTRIC
I
DOWNSTOP ECCENTRIC
(Locknut on Other End)
RETAINING PAWL
T.o Check
Disengage function clutch. Take up backlash in
ratchet wheel so that clearance between feed pawl
and ratchet tooth is at minimum. Measure clear-
ance. Repeat for other ratchet wheel.
(1) Requirement·
Clearance between feed pawl and ratchet tooth
L----------------------- Min 0. 020 inch---Max 0. 040 inch
on side where clearance is least.
(2) Requirement
Pawl should feed one tooth at a time.
To Adjust
Position downstop eccentric with locknut loosened.
Tighten locknut.
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