Upload
sunil-talekar
View
1.835
Download
7
Tags:
Embed Size (px)
DESCRIPTION
Citation preview
KNITTING NEEDLE
By Suneel Talekar- sr. Faculty- SOFT-Pune
Knitting needleTYPES
THE BEARDED NEEDLE
3 TYPES OF KNITTING NEEDLES
THE COMPOUND NEEDLE
THE LATCH NEEDLE
the hook opening and closing device
a system allowing the needle to
move and form the loop.
the hook, which takes and retains the thread to be
looped
• The bearded or spring needle was the first type of needle to be produced.
• It is the cheapest and simplest type to manufacture as it is made from a single piece of metal
• The bearded needle is essentially a frame needle, the needles being fixed to move
Breaded needleFEATURES
• The head, where the stem is turned into a hook to draw the new loop through the old loop.
• The beard, which is the curved downwards continuation of the hook that is used to separate the trapped new loop inside from the old loop as it slides off the needle beard.
• The stem, around which the needle loop is formed.
• The eye, or groove, cut in the stem to receive the pointed tip of the beard when it is pressed, thus enclosing the new loop.
• The shank, which may be bent for individual location in the machine or cast with others in a metal ‘lead’.
Breaded needlePARTS
BREADED NEEDLE AND KNITTING MACHINE PARTS
Breaded needle
Knitting action
The rest position Backward swing and overlap shog (b, c). The return swing and second rise (c, d).
Pressing (e) Landing (f). Knock-over and underlap shog (g)
Breaded needle
Knitting action
Breaded needle
Knitting action
1. The needle is in the (so-called) rest position, with the previously formed loop (a) held on its stem and covered by the hook.
2. The loop is cleared from the needle hook to a lower position on the needle stem.3. The new yarn (b) is fed to the needle hook at a higher position on the needle stem than the
position of the previous (‘old’) loop.4. The yarn is formed into a ‘new’ loop.5. The hook is closed, enclosing the new loop and excluding and landing the old loop onto the
outside of the closed hook.6. The new loop (b) is drawn through the head of the old loop (a). Simultaneously the old loop
slides off the closed hook of the needle and is cast-off or knocked-over.7. The old loop now hangs from the feet of the fully formed new loop and the knitting cycle
starts again.
12 3 4
56 7
Breaded needle
Advantages Limitation
• Less expensive• Strain on yarn is less• No possibility of fluff or
lint accumulation on needle• Good for warp knitting
machine
• Required an additional element to close the beard during knitting
• High wear and break easily• Limiting productivity• A knitting section occupies
a considerable amount of space
• Individual loop formation has to be achived by a loop forming element, this leads to a more complicated
Breaded needle
Latch Needle Characteristics: 1. Most widely used in weft knitting.2. More expensive needle than the bearded needle.3. Self acting or loop controlled.4. Work at any angle.5. Needle Depth determines the loop length.6. Variation of the height of reciprocating produces knit, tuck or miss stitch.
Characteristics
Latch needle
The Hook: The hook which draws and returns the new loop.The slot or Saw Cut: This slot receives the latch blade.
Features-hook
Latch needle
Features
The Cheeks or Slot Walls: It is either punched or riveted to fulcrum the latch blade.The Rivet: The rivet which may be plain or threaded. This has been dispensed with on most plated metal needles by pinching the slot walls to retain the latch blades.The latch blade: This latch blade locates the latch in the needle.
Latch needle
The latch blade: This latch blade locates the latch in the needle.
Features
Latch needle
The latch spoon: The latch spoon is an extension of blade and bridges the gap between the hook and stem.
Features-latch and latch spoon
Latch needle
7. The stem: The stem of latch needle carries the loop in the clearing on rest position.8. The Butt: Butt of latch needle enables the needle to be reciprocated.9. The Tail: The tail is an extension below the butt giving additional support to the needle and keeping the needle in its trick
Features
Latch needle
Latch needle
Latch needle
Knitting action
Latch needle
Knitting action
Latch needle
The rest position: The head of the needle hook is level with the top of the verge of the trick. The loop formed at the previous feeder is in the closed hook. It is prevented from rising as the needle rises, by holding-down sinkers or web holders that move forward between the needles to hold down the sinker loops.
Latch needleKnitting action
Latch opening: As the needle butt passes up the incline of the clearing cam, the old loop, which is held down by the sinker, slides inside the hook and contacts the latch, turning and opening it.
Latch needleKnitting action-latch opening
Clearing height: When the needle reaches the top of the cam, the old loop is cleared from the hook and latch spoon on to the stem. At this point the feeder guide plate acts as a guard to prevent the latch from closing the empty hook.
Latch needleKnitting action-clearing height
Yarn feeding and latch closing: The needle starts to descend the stitch cam so that its latch is below the verge, with the old loop moving under it. At this point the new yarn is fed through a hole in the feeder guide to the descending needle hook, as there is no danger of the yarn being fed below the latch. The old loop contacts the underside of the latch, causing it to close on to the hook.
Latch needleKnitting action-yarn feeding
Knocking-over and loop length formation: As the head of the needle descends below the top of the trick, the old loop slides off the needle and the new loop is drawn through it.
Latch needleKnitting action-cast off
Advantages Limitation• Major advantages of being self
acting or loop controlled, so that individual movement and control of the needle enable stitch selection to be achieved.
• Ideally suited for use with computer controlled electronic selection devise.
• Latch needle can operate at any angle.
• Variation of the height of vertical can produce knit, miss and tuck loop which helps to manufacture different design fabrics.
• Latch needle are thick and rigid, so any deflection id design effect on fabric
• Needle deflection is difficult• It imposes a certain strain on
yarn• There is also possibility of fluff
or lint accumulation on the latch due to rubbing of the yarn on needle
Latch needle
Latch needle Spring bearded needle
1. It contains a hook portion at the top & a latch reverted at certain distance from the needle head.
1. This needle consists of a top hook curved downwards with a finished tip.
2. The main element of knitting is latch.
2. The downward continuation is called beard.
3. The latch needles are self-acting.
3. The spring bearded needles are not self-acting type.
4. Do not need outside agency to close the hook.
4. It requires pressure to close the needle.
Latch needleDifference between latch and bearded
needle
Latch needle Spring bearded needle5. Machine gauge is coarser then spring bearded needle.
5. Machine gauge is finer then latch needle.
6. This one is not simple type needle.
6. Simple type of needle.
7. It has reduced stroke. 7. It has more stroke than latch needle.
8. Most widely used in weft knitting.
8. More widely used in circular single knitting.
9. Complicated operating system.
9. Easy operating system.
10. The latch needle is more expensive & intricate needle.
10. The spring bearded needle is less expensive than latch needle.
Latch needleDifference between latch and bearded
needle
The tubular pipe needle has its tongue sliding inside the tube of the open hook.The open-stem ‘pusher type’ or slide needle
Compound needleTypes
tongue sliding pusher type
Features
Compound needle
• Compound needles consist o two separately controlled parts- the open hook and the sliding closing element (tongue, latch, piston, plunger)
• It is most popular in warp knitting machines
• Strain in not put on the yarn• Both members of compound
needle have a straight, thus knitting speed can be increased.
• These needle are very expensive
Thanks