Knitting technology, Third Edition

19.11.4
Modern take-down systems
Modern machines have a computer-programmed, positively-driven takedown
system whose operation is synchronised with that of the requirements of the knit-
ting programme and provides pre-determined fabric tension as required. Some-
times, small sub-rollers provide a nip immediately below the gap in the needle beds.
The main control is provided by the nip formed by the takedown roller and the
counter roller that presses against its surface. The counter roller is segmented, con-
sisting of individual rollers that are each spring-adjusted.

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Knitting technology
The roller drive speed can be selected from as many as 31 possibilities and can
be stopped during needle bed racking and rib loop transfer, or it can be reversed
to achieve zero fabric tension whenever required during the knitting programme.
19.11.5
Control of the fabric during knitting
The production of width-shaped garment pieces requires different or additional
facilities to those used when knitting constant-width garment pieces joined by draw-
thread separation. No one device alone appears to provide for all conditions of
fabric takedown when knitting to shape.
When changing from a narrow width at the end of one garment panel and recom-
mencing on a wider starting width for the next panel, with normal takedown rollers
there will be a lack of takedown tension and fabric control at the selvedges, even
with a draw-thread connection. If the pieces are not connected together, there will
be no takedown tension. The most common solution is to employ a takedown comb
in addition to the conventional takedown rollers; this rises to engage its pins with
the set-up courses of the new garment piece. As knitting continues, it guides the
fabric until it engages with the takedown roller, which then takes over control of
the knitted panel. With separated garment piece knitting it is also necessary to
employ thread cutters and trappers, otherwise yarn ends will wrap around the
rollers.
Shima
have a new computer-controlled pull-down system for their 
FIRST Whole-
Garment
machines. The front and back of the garment each has a separate take-
down panel of tiny pins, each section of which can be individually controlled for
specific tension. This results in a more dimensionally-accurate garment; for example
by allowing shoulder lines for set-in sleeves to be positioned over the shoulders and
towards the back.