1. Guides and guide bars
Guides are
thin metal plates drilled with a hole in their lower end through a warp end may
be threaded if required. The guides are held together at their upper end in a
metal lead of 1 inch width and are spaced in it to the same gauge as the
machine. The leads in turn are attached to a horizontal bar to form a complete
guide bar assembly bar, so that the guides hang from it with each one occupying
a position at rest midway between two adjacent needles. In this position the
needles do not receive the warp yarns.
The needles only receive the warp yarns in their hooks if the guides wrap or lap the yarns across the needles. For the purpose, the guide bars are given a compound lapping movement. All guides in a conventional guide bar produce an identical lapping movement at the same time and therefore have requirements of same warp tension and rate of feed although yarns may differ in colour and composition. But the two guide bars may have different lapping movement where requirement of warp feed and warp tension may vary also.
The needles only receive the warp yarns in their hooks if the guides wrap or lap the yarns across the needles. For the purpose, the guide bars are given a compound lapping movement. All guides in a conventional guide bar produce an identical lapping movement at the same time and therefore have requirements of same warp tension and rate of feed although yarns may differ in colour and composition. But the two guide bars may have different lapping movement where requirement of warp feed and warp tension may vary also.
2. Needle and needle bar
In warp
knitting, all the needles move up and down together for loop formation, i.e.,
all the loops in a course are made simultaneously. So all the needles are
connected/fixed to a bar called needle bar and the needle bar is lifted
up and lowered down by means of a cam fitted outside the machine, generally at
the driving side. Needles are set in tricks cut in the needle bed of the
machine.
3. Closure bar (or Presser bar)
In order to close the hook for casting-off of
the old loop in Tricot machine, some closing element (Presser bar) is must. The
elements needed in Tricot machine are set in a separate bar across the full
width of the machine which also get motion from a cam or crank fitted on the
main shaft. The presser bar closes the hook of the needle when the same moves downward
after catching of the new yarn for loop formation.
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