of ordinary yarn.
CHAPTER IX. THE ROVING FRAME
The process of doubling ends with the last drawing frame, but there
still remains a process by means of which the drafting of the
slivers and the parallelization of the fibres are continued. And, in
addition to these important functions, two other equally important
operations are conducted simultaneously, viz., that of imparting to
the drawn out sliver a slight twist to form what is known as a
"rove" or roving, and that of winding the rove on to a large rove
bobbin ready for the actual spinning frame.
The machine in which this multiple process is performed is termed a
"roving frame." Such machines are made in various sizes, and with
different types of faller mechanism, but each machine is provided
for the manipulation of two rows of bobbins, and, of course, with
two rows of spindles and flyers. These two rows of spindles, flyers,
and rove bobbin supports are shown clearly in Fig. 18, which
represents a spiral roving frame made by Messrs. Douglas Fraser &
Sons, Ltd., Arbroath.
Each circular bobbin support is provided with pins rising from the
upper face of the disc, and these pins serve to enter holes in the
flange of the bobbin and thus to drive the bobbin. The discs or
bobbin supports are situated in holes in the "lifter rail" or
"builder rail" or simply the "builder"; the vertical spindles pass
through the centre of the discs, each spindle being provided with a
"flyer," and finally a number of plates rest upon the tops of the
spindles.
[Illustration: FIG. 18 ROVING FRAME _By Permission of Messrs.
Douglas Fraser & Sons, Ltd_.]
A roving machine at work is shown in Fig. 19, and it will be seen
that the twisted sliver or rove on emerging from the drawing rollers
passes obliquely to the top of the spindle, through a guide eye,
then between the channel-shaped bend at the upper part of the flyer,
round the flyer arm, through an eye at the extreme end of either of
the flyer arms, and finally on to the bobbin. Each bobbin has its
own sliver can (occasionally two), and the sliver passes from this
can between the sides of the sliver guide, between the retaining
rollers, then amongst the gill pins of the fallers and between the
drawing (also the delivery) rollers. Here the sliver terminates
because the rotary action of the flyer imparts a little twist and
causes the material to assume a somewhat circular sectional form.
From this point, the path followed to the
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