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BAHIR DAR UNIVERSITY
Ethiopian Institute of Textiles and Fashion Technology(EITEX)
SEMINAR ON KNITTING MACHINES FOR FULLY FASHIONED CLOTHING
PREPARED BY: SELAMU TEMESGEN SUBMITTED TO : Dr.S.Kathirrvelu (Professor Textile Tech.
KNITTING MACHINE FOR FULLYFASHIONED GARMENT
Introduction to Knitting: Knitting is a process of fabric manufacturing by converting yarn into loop form and then these loops interlock/inter-mesh/interloped together .
• Knit garments: Knit garments are basically three types: • Cut and sew knit garments. • Fully Fashioned shape knitwear. • Complete knitted garments Cut and Sew knit garments:
• The cut and sew technique is by far the simplest method of garment construction whereby individual panel shapes are cut to size from panels (V bed or flat bed) or from a long length of fabric or cloth (circular knitting machines).
Fully Fashioned Shaped Knitwear: • 1) Shaped knitwear is engineered to size and
shaped at the point of knitting. • 2) It is very distinctive and easily identifiable by
the “fashioning marks” which normally run parallel to the garment seams.
• 3) The garment panels are assembled using “cup seaming” and “linking” where usually the garment sides, sleeves and underarms are cup seamed and the shoulders and collars are linked.
• 4) The difference between linking and seaming is that with linking a stitch per stitch joint results whereas cup seaming stitches the edges of the fabrics together.
Name of Fully fashioned knit garments: 1) . Sweater 2) . Cardigan 3). Tights 4) . Stockings 5) . Lingerie, etc
• Fully Fashioned Knitwear: • Fully fashioning is a process of shaping a knitted structure by
increasing or decreasing the number of needles or Wales where the individual pieces are more engineered so that each garment piece is made with no extra fabric and the pieces are basically knitted together at the seams.
• In this case each piece is shaped using techniques specific to knitwear by using special stitches, making lines of loops shrink and grow depending on where more length is needed and where not.
• Example- Sweater, Pullover, Cardigan etc.
The production procedure of a fully fashioned knitwear
Fully fashioned knitting machines
Fully-fashioned knitting machines are flat knitting machines that produce custom pre-shaped pieces of a knitted garment.
The most commonly used fully fashioned knitting
machines are 1. Straight bar frame machines 2. Flat machines- manual&computerizad 3.Circular machine
Hand Loom Flatbed Knitting Machine Hand loom flatbed knitting machine is a smaller and less costly type of machine that does not run automatically.
• Instead, it is manually operated to produce sweater panels. • The operator follows the knitting instructions given, adjusts the cam,
and knits each row accordingly. • It is more labor intensive than a computerized machine but still more
efficient than hand knitting or hand crochet
Fig .Hand Loom Flatbed Knitting Machine
The development of the straight bar frame • The straight bar frame is, with a number of later
improvements and developments, recognizable as a direct descendant of William Lee’s hand frame.
• William Cotton of Lough transformed the hand controlled power-driven rotary frame into the high-speed automatic fashioning multi-head straight bar frame.
• The modern automatic straight bar frame with its fully-programmed garment-knitting sequence was around 1953.
Fig. Sixteen-head plain straight bar frame having a conveyer for transporting the rib ends to each head [Iropa)
• The fully-fashioning process allows the separate creation of shaped front and back body parts and sleeve parts by increasing or decreasing the number of loops and this eliminates the cutting operation.
• However, because all parts of the garment are knitted separately, the fully fashioned knitting still requires a post sewing or linking process.
• Linking is defined as a process of joining side seams or edges of fabric pieces together with a row of knitting on a linking machine
• To achieve fully fashioned knitting, loop transference is necessary.
• The loop transference is the process that moves stitches (i.e., loops) from the needles on which they were made to other needles .
• Following figure illustrates the mechanism of loop transference on a V-bed flat knitting machine. The fully-fashioning process allows the separate creation of shaped front and back body parts and sleeve parts by increasing or decreasing the number of loops
a. The delivering needle is raised by a cam in the carriage. The loop is stretched over the transfer spring.
b. The receiving needle is raised slightly from its needle bed. The receiving needle enters the transfer spring of delivering needle and penetrates the loop that will be transferred.
c. The delivering needle retreats leaving the loop on the receiving needle. The transfer spring opens to permits the receiving needle to move back from its closure. Finally, loop transference is completed.
Fig. Mechanism of loop transference on V-bed flat knitting machine
Knitting action of the plain straight bar frame
• Figure below shows the cross-section of the knitting head containing the following elements:
• A .Bearded needle, having a cranked end for location in the tricked and drilled needle bar.
• B. Sinker – only one between every other needle space – with a reinforced back and, at the front, a ‘catch’ to sink the yarn around the needles, and a ‘neb’ to separate the old and new loops until knock-over.
• C. Divider, occupying each remaining space, usually having the same shaped front as the sinker but with an extended tail at the back.
• D. Knocking-over bit – one directly beneath each sinker and divider – having a ‘throat’ for holding the loops and a ‘nose’ for knocking-over.
• E. Needle bar, having a compound horizontal and vertical movement.
• F. Striking jack, fulcrummed at its lower end, each one with its ‘nose’ resting on a sinker back, and a ‘spring’ exerting pressure on its ‘tail’.
• G. Catch bar, extending the full width of the knitting head, having forward and backward, as well as vertical, movement.
• H. Yarn carrier, which traverses in alternate directions across the head from one course to the next – up to six carriers may be available.
• The carrier is connected to a reciprocating carrier rail by friction, and when the carrier is arrested by its carrier stop, the carrier rail completes its full traverse, driven by the coulier cam and punching through the carrier friction.
• J. Falling bar, which is a stop that cushions the advance of the sinkers and dividers
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