Sinker:

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• Sinker
• Sinker is a thin metal plate which placed in the
  middle position of each two needle. These sinkers
  are parrallely attached in 1? lead. Sinker acts
  in holding down, knocking over and supporting the
  fabric. When the needle is moved downwards then
  sinker throat holds down the fabric and belly
  knocks over.
• Guides and guide bar
• Guides are mounted on guide bar. The threads are
  passed into the guides of the guide bar. Guide
  bar gets shogging and swinging movements from
  main shaft and pattern chain.0,1, 2, 3, or 4
  guide bars are used in tricot m/c. tricot m/c
  with two guide bat are mostly used but tricot m/c
  with more number of guide bar are less used.

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• FeatureRachel warp knitting m/c
• 1. Rachel m/cs used latch needles together
  with a wire or blade
• 2. It has a gauge expressed in needles per
  2inches (5cm) so that for example a 36 gauge
  Rachel m/c will have 18npi
• 3. Their chain links are usually numbered in
  even numbers 0, 2, 4, .etc generally with 2
  links/course
• 4. Rachel sinkers only performs the function
  of holding down the loops whilst the needles rise
  
• 5. Rachel sinkers are not joined together by
  a lead across their ends nearest to the needle
  bars so they can move away clear of the needles
  towards the back of the m/c for the rest of the
  knitting cycle
• 6. The fabric is drawn downwards from the
  needles, almost parallel to the needle bar at an
  angle of 120-160 by a series of take-down
  rollers.

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• 7. The warp beams are arranged above the
  needle bar, centered over the rocker shaft, so
  that the warp sheets pass down to the guide bars
  on either side of it
• 8. The beams are placed above the m/cs so
  that it is accessible at the front for the fabric
  inspection
• 9. At least four 32? diameter beams or large
  numbers of small diameter pattern bars
• 10. The guide bars are threaded, connecting
  with the middle bars and working outwards from
  the eitherside of the rockershaft
• 11. The guide bars are numbered from the
  front of the m/c
• 12. The needle trick plate acts as a fabric
  support ledge and knockover surface.

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• Knitting elements of Rachel m/c
• Needle
• Most of the modern Rachel knitting m/cs
  built today use compound needle. Many m/cs,
  however, are still equipped with latch needles.
  Compound needles are set as in Tricot m/cs into
  trick which are cut into the needle bar and both
  main parts and closing elements are driven
  separately to open and close the hook.
• Trick plate
• The loop formation in a Rachel m/c takes
  place on the upper edge of the trick plate. This
  bar can be considered as a needle bed, since the
  needles are placed in tricks cut into it.

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• The sinker
• The sinker like the latch needles are
  cust in units 1? long placed in the spaces
  between the needles. They are used to ensure that
  the fabric stays bowl while the needle rise to
  form their next knitting cycles. The sinker of
  Rachel m/cs are therefore only of secondary
  importance

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• The latch guard
• A steel wire which are extended from one
  ends to the others parallel to the needle. During
  loop formation, the fabric loops open needle
  latch but sometimes closed the needle hook. As a
  result a closed hook cannot feed the new yarn.
  This latch guard placed needle hook side. So that
  the latch cannot close the hook and helps to open
  the needle hook.
• Guide Guide bar
• The number of guide bar in Rachel m/c is
  more. Sometimes are of more than 70. Two types of
  guide bar are used-
• Fully threaded guide bar Used to produce ground
  fabric and yarn pass to each guide.
• Partially threaded guide bar According to the
  design. One yarn is passed in each bar for each
  pattern repeat. Thread pass where design placed.

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Difference between Tricot Rachel warp knitting
m/c Tricot
Raschel

1. In the past, bearded needle was used but now a
   days compound needle used
2. M/C gauge expressed in needle per inch
3. Chain link numbering 0, 1, 2, 3, .etc
4. Function of sinker is holding down, knocking and
   supporting the fabric
5. The fabric is drawn away towards the batching
   roller almost at right angles to the needle bar
6. The warp beams are accommodated in an inclined
   towards the back of the m/c there the top
7. The warp sheets pass over the top of the guide
   bar rockershaft to their tension
8. Mechanical attention is carried out at the front
   of the m/c
9. The guide bars are numbered from the back towards
   the front of the m/c
10. High speed production

1. Rachel m/c used latch needle together with a wire
   or blade
2. M/C gauge expressed in needle/2inch
3. Chain link numbered in even numbers 0, 2, 4,
   .etc
4. Sinker performs the function of holding down the
   loops whilst the needle rise
5. The fabric is drawn downwards from the needles
   almost parallel to the bar at an angle of
   120-160
6. The warp beams are arranged above the needle bar
   centered over the rocker shaft
7. The warp sheets pass down the guide bar
8. Mechanical attention is carried out at the back
   of the m/c
9. The guide bars are numbered from front of the m/c
10. Low speed production

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Tricot warp knitting M/C
Rashel Warp knitting M/C
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Features The crochert warp knitting m/c

• A single horizontal needle bar whose simple
  reciprocating action can be used to operate
  individually tricked latch, carbine or
  embroidery needles. The patent or carbine bearded
  needle is used for fine structures and has a side
  ways crimped beard placed in a permanently-pressed
  position. Although warp threads can only be fed
  into the beard from the left, the old overlaps
  are automatically cleared and landed by the
  movement of the needle. The needles can be
  arranged for coarser gauges or for fancy
  set-outs, when the floating inlay threads may be
  cut to produce separated fringed edgings.
• 2. No sinkers instead a fixed hold back bar is
  fitted in from of the knock over verge to prevent
  the fabric moving out with the needles
• 3. The closed lap pillar stitches and inlay
  threads controlled and supplied as separate warp
  and weft respectively

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• 4. The weft yarn, often placed above and towards
  the back of the m/c, supplying the carrier tubes
  which are clipped to the spring loaded inlay
  bars.
• 5. Special arrangements/attachments are available
  for producing fancy effects such as cut or uncut
  fringe edges, pile, braiding and snail shell
  designs.
• 6. Gauge often expressed in needles per
  centimeter are between 2 and 10 (E5 to E24)
• 7. Knitting widths of crochet m/cs may vary
  between 16 and 122 inches.
• 8. M/C runs at speeds between 200 and 350
  courses per minute
• 9. Crochet m/cs can process a range of filament
  yarn from 20dtex to 1000dtex
• 10. The warp yarn is often placed low at the
  front of the m/c.

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Fig Crochert warp knitting m/c
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WEFT KNITTING

• Types of weft knitting m/c
• According to the end product, the weft knitting
  m/c may be broadly classified as either
• Fabric m/cs
• Garment length m/cs
• According to their frame design and needle bed
  arrangement, the weft knitting m/c may be broadly
  classified as either
• Straight bar frame m/cs
• Flat knitting m/cs
• Circular knitting m/cs

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Features of fabric m/cs

• Large diameter, circular, latch needle m/cs (also
  known as yarn goods or piece goods) knit fabric,
  at high speed.
• The fabric is manually cut away from the m/c
  usually in roll form after a convenient length
  has been knitted.
• Most fabric is knitted on circular m/cs either
  single-cylinder (single jersey) or cylinder and
  dial (double jersey) of the revolving needle
  cylinder type, because of their high speed and
  productive efficiency
• Sinker wheel and loop wheel frames could knit
  high quality specialty fabrics with bearded
  needles although circular m/cs employing bearded
  needles are now absolute, the production rates of
  these m/cs were uncompetitive

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• Unless used in tubular body-width, the fabric
  tube requires splitting into open-width
• The fabric is finished on continuous finishing
  equipment and is cut-and-sewn into garments or it
  is used for household and technical fabrics
• The productivity and patterning facilities of
  fabric m/cs vary considerably.
• Generally cam settings and needle set-outs are
  not altered during the knitting of the fabric

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Flat knitting m/c Feature

• 2 stationary needle bed in flat knitting m/c
  arranged in an inverted V formation
• Latch needle is used
• Angular cam of a bi-directional cam system used
• There is a separate cam system for each needle
  bed
• The two cam systems linked together by a bridge,
  which passes across from one needle bed to the
  other
• Carriage with determined yarn carrier issued
• Cam system is attached to bottom side of carriage
  
• The flat m/c is the most versatile of the weft
  knitting m/c
• Fabric produce with finer to coarser yarn
• The operation and supervision of the m/c is
  simple
• The stitch length range is wide and possibly of
  changing the m/c gauge
• Trimmings, edging, collars, to shaped panels and
  integrally knitted complex garments and other
  articles

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• Classification of circular knitting m/c
• 1. Circular bearded needle single-jersey fabric
  machine
• 2. Revolving cylinder latch needle machine
• 3. Circular garment length machine
• 1. Circular bearded needle single jersey fabric
  machine
• Types of machines are divided into two
  types-
• a) Sinker wheel machine or French/Terrot type m/c
• b) Loop wheel frame or English type m/c
• Both of them have the following common
  features-
• Needles are fixed in a revolving circle on needle
  bed
• Knitting action is entirely achieved by ancillary
  elements moving yarn and loops along the needle
  stem
• Here tubular fabric is knitted with its technical
  back facing outward
• Low productivity but has an ability to produce
  unusual and super-quality knitted structures
• 2. Revolving cylinder latch needle machine
• There ate two main types of revolving
  cylinder latch needle machine, namely-
• Open top or sinker top or single jersey m/c
• Cylinder dial m/c or double-jersey mc/

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Knitted Loop

• Knit Loop
• Tuck Loop
• Miss Loop

Md.Ahashan Habib
B.Sc in Textile Engineering(DU)
6/19/2016
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• Tuck stitch
• A tuck stitch is composed of a held loop, one or
  more tuck loops and knitted loops.
• It is produced when a needle holding its loop
  also receives the new loop which becomes a tuck
  loop, because it is not intermeshed through the
  old loop.
• Miss/Float stitch
• A float stitch is composed of a held loop, one or
  more float loops and knitted loops. It is
  produced when a needle holding its old loop fails
  to receive the new yarn that passes, as a float
  loop, to the back of the needle and to the
  reveres side of the resultant stitch.
• The miss stitch can occur accidentally as a fault
  due to incorrectly set yarn feeders.

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• Methods to obtain Tuck/Held loops
• 1. Without casting off operation in loop forming
  cycle , i.e. Tucking of the latch
• 2. Without clearing operation in loop forming
  cycle, i.e. Tucking in the hook
• 3. With switching a needle out of action from
  loop forming cycle
• Tucking on the latch
• When tuck stitch formation is performed without
  casting-off and sinking are excluded from the
  loop formation cycle. In this case, the needles 4
  and 7 knit the loops 3 and 6, while the needle 5
  performs all the operations up to joining and
  stops. Then a new yarn 2 is fed in its hook and
  this will be the tuck loop, the old loop 1
  remains on the closed latch and this will be the
  held loop.
• After the needle 5 is lifted for clearing, in the
  following loop formation cycle it receives a new
  yarn and knits a loop from it, casting-off upon
  it old held loop 1 and the tuck loop 2
• Step of forming held loop in 5 needle

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Difference between Warp knitting Weft
knitting.Warp Knitting Weft
Knitting

• The loops are produced to the length of fabric
• The threads runs in the vertical direction
• Each loop in the horizontal direction is made
  from a different thread
• It is elastic to the length
• Its elasticity is less
• Yarns are supplied from beam
• At least one yarn is needed for each needle
• Less shrinkage

• The loops are produced to the width of the fabric
  
• The threads runs in the horizontal direction
• A horizontal row of loops can be made by using on
  thread
• It is elastic to the width
• Higher elasticity
• From cone
• Any number of needle are required for on e yarn
• More/Higher shrinkage