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Rear Pressure Lever
Feed Rof.( Tension Springs
Carriage Release Universal Bar
j , . . .
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...
Front Pressure Lever
Platen Guide Shaft
Center Support
Shaft Eccentric
Figure 34.
Feed Roll Mechanism
on the paper bai I pivot shaft and the paper table tie rod. Arms
from the front paper table serve as latches to hold the rear
paper table to the tie rod shaft. As the paper is inserted into
the machine, an adjustable guide mounted on the rear paper
table serves to position the paper for its left margin position.
Next the paper contacts the rear rolled edge of the deflector
(Fig. 33). This edge guides the paper into the "V" formed by
the rear feed rolls and the platen. The bottom of the deflector
contains lugs that stradle the feed roll release cam shaft and
serve to position the deflector. Support lugs on the rear pres-
sure levers control the distance between the deflector and the
pl~ten. Sixteen inch and longer deflectors are connected by
a rod which is spot-welded within the rolled edge.
A single piece deflector, designed to faci Ii tate manufacture
is in all 16" machines above serial number 613547. Horizontal
and rotational movement of the single piece deflector is pre-
vented by two formed I ugs on the rear of the deflector. These
lugs seat in undercuts on the feed roll release cam shaft. The
former spot-welded lug-type deflector wi II remain avai lable
for replacement on machines prior to this change. I f it is de-
sirable to con'vert to the new single piece deflector on machines
prior to this change, it will be necessary to replace the feed
roll release cam shaft. The new shaft is interchangable with
the former shaft.
Rotation of the platen causes the paper to be fed between the
re~r feed rolls and the platen. Feed rolls are spring loaded
against the platen and are rotated by their friction on the paper
or platen (F ig. 33). As the front edge of the paper leaves the
rear feed rolls, it is guided by the deflector unfil it moves in
between the front feed rolls and tbe platen. Both front and
rear feed rolls now hold the paper firmly agairist the platen
and insure its rotation wifh the platen.
Feed ro II pressure is supplied by applying a twist to flat torsion
springs (Fig. 34). The ends of these springs are mounted in
15
slots in plastic bushings which are molded to the pressure
levers. Feed ro lis mount on shafts whose ends mount in these
pressure levers.
Feed roll pressure is determined by the
amount of twist put into the spring by their adjusting screws.
The ends of the springs attempt to rotate the plastic bushings
and pressure levers, and in this manner supply a constant up-
ward pressure to the feed rolls. The pressure lever bushings
are mounted in holes in the feed roll cradles and the cradles
are mounted to the feed roll release cam shaft and the platen
guide shaft. Left to right motion of the cradles is restricted
by a feed roll center support on one side, and a spring clip
on the platen guide shaft on the other side. Left to right
motion of the pressure levers is restricted by the
cradle~
which
are held on the plastic bushings by spring clips.
Each feed roll is molded to a hub and two hubs are mounted
on each feed roll shaft. This arrangement gives maximum
bearing surface for the rotation of each feed roll. The feed
roll shaft is mounted in "D" shaped holes in the pressure levers.
These holes keep the shaft from rotating. The shaft has a spring
loaded plunger at one end for ease of removal and replacement.
Feed roll hubs and rear feed roll shafts have been redesigned
to reduce the length of the feed roll hub by approximately
1/4 inch. This change appears on machines above serial num-
ber 519557. Feed rolls have been placed in the center of the
hub (Fig. 34) and the hub assemblies are retained on the shaft
by two adjustable clips which permit adjustment to reduce end
play of the feed rolls to a minimum. The clips are also used
to ho Id the shaft in place in the rear pressure levers. The
front feed rolls are sti II mounted on the shaft with the spring
plunger. It is necessary to use this shaft in order to hold the
front pressure levers in place.
The feed roll center support is mounted on the carriage bed
and helps to position the feed roll cradle assemblies (Fig. 35).
In addition, the center support provides rigid support for the
feed roll release cam shaft and the center platen guide shaft
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