tance is "reach."
On emerging from the drawing rollers, the combed slivers pass
between slicking rollers, and then approach the sliver plate which
bridges the gap between the slicking rollers and the delivery rollers,
and by means of which plate two or more individual slivers are
diverted at right angles, first to join each other, and then again
diverted at right angles to join another sliver which passes
straight from the drawing rollers and over the sliver plate to the
guide of the delivery rollers. It will thus be seen that a number of
slivers, each having been drawn out according to the degree of draft,
are ultimately joined to pass through a common sliver guide or
conductor to the nip of the delivery rollers, and thence into a
sliver can.
The push-bar drawing illustrated in Fig. 17, or some other of the
same type, is often used as the first drawing frame in a set. With
the exception of the driving pulleys, all the gear wheels are at the
far end of the frame, and totally enclosed in dust-proof casing. The
set-on handles, for moving the belt from the loose pulley to the
fast pulley, or _vice versa_, are conveniently situated, as shown,
and in a place which is calculated to offer the least obstruction to
the operative. The machines are made with what are known as
"two heads" or "three heads." It will be seen from the large
pressing rollers that there are two pairs; hence the machine is a
"two-head" drawing frame.
The slivers from the first drawing frame are now subjected to a
further process of doubling and drafting in a very similar machine
termed the second drawing frame. The pins in the gills for this
frame are rather finer and more closely set than those in the first
drawing frame, but otherwise the active parts of the machines, and
the operations conducted therein, are practically identical, and
therefore need no further description. It should be mentioned,
however, that there are different types of drawing frames, and their
designation is invariably due to the particular manner in which the
fallers are operated while traversing the closed circuit. The names
of other drawing frames appear below.
Spiral or screw gill;
Open link chain;
Rotary;
Ring Carrier
Circular.
For the preparation of slivers for some classes of yarn it is
considered desirable to extend the drawing and doubling operation in
a third drawing frame; as a rule, however, two frames are considered
sufficient for most classes
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