平针织物关边

1、1Welts, garment sequences and knitting to shapeLesson 12212.1 The welt 关边关边A welt is an attractive and secure edge of a knitted article that helps to prevent laddering or unroving of a structure.12.1.1 The plain fabric welt 平针织物关边平针织物关边On machines with no facilities for rib welt （罗纹关边） sequences, th

2、e plain fabric is formed into either a turned-over inturned-welt or a mock rib welt （假罗纹关边）. Sometimes the curling edge of plain fabric is used as the start of a garment or the curl of a collar instead of a welt.312.1.2 The inturned welt 折边折边The inturned welt is used particularly for manufacturing l

3、adies hose and sports socks on circular machines (Fig. 12.1) and some knitwear on Cottons Patent machines (Fig. 12.2). Jacks or hooks collect the sinker loops of the third course or the set-up course and hold them, drawing the fabric away until sufficient has been knitted for the double-thickness we

4、lt.4Fig.12.2: Turned welt on bearded needle machine.Fig.12.1 Turned welt on latch needle machine.512.1.3 Accordion top 阿考丁起口阿考丁起口 An accordion top (Fig.12.3), welt and mock rib, can be produced on single-cylinder half-hose and sock machines, and on other machines using a single set of needles in a t

5、ubular arrangement. Elastomeric yarn is laid-in to odd needles only for a few courses. The elastomeric yarn is then usually inlaid on a two-tuck two-miss or a one-and-one basis at each course or alternate courses for a number of courses. 6Inlaid rubber threadsFig.12.3 Accordion welt top.712.2 Rib we

6、lts 罗纹关边罗纹关边 Most fully-fashioned and stitch-shaped underwear and outerwear garments, half-hose, and socks have ribbed borders containing a welt sequence that is produced by causing the sets of needles to act independently of each other after the 1x1 rib set-up course.8 Three types of welt are possi

7、ble when needles are arranged in 11 rib set-out. These are:n1 The tubular or French welt.n2 The roll or English welt.n3 The racked welt.9 12.2.1 The tubular welt 筒状关边筒状关边 The tubular welt (Fig.12.4) is the most popular welt because it is a balanced structure that is reversible, lies flat, can be ext

8、ended to any depth and is elastic. Its only disadvantage is that it can become baggy during washing and wear unless knitted tightly. 1012.2.2 The roll welt 折边关边折边关边 The roll welt (Fig. 12.5) is produced by knitting approximately four courses on one set of needles only whilst continuing to hold the s

9、etting-up course of loops on the other set of needles. 1112.2.3 The racked welt 波纹关边波纹关边 The racked welt (Fig.12.6) is neat and inconspicuous, rather like the set-up course of hand knitting in appearance, and is favoured for collars and other trimmings. 12Fig.12.4 Tubular welt Fig.12.5 Roll welt.Fig

10、.12.6 Racked welt1312.3 Separation 分离横列分离横列 If the string of garments is separated by cutting, there is a danger of either the welt being damaged or of unwanted yarn not being removed.1.in the form of a draw thread course, preceding the first course of the new garment. The draw thread is usually a s

11、mooth strong yarn.2.the press-off draw thread construction. 3.to knit a number of courses in a soluble yarn such as alginate. 1412.4 Imparting shape during knitting The three methods of width shaping are: n1 varying the number of needles in action in the knitting widthn2 changing the knitting constr

12、uctionn3 altering the stitch length.15 Wale fashioning is the normal manner of shaping (symmetrically or a symmetrically) on straight bar frames (Figures 12.7 and 12.8). Fig.12.7 Wale fashioning (narrowing) Fig.12.8 Wale fashioning (widening) Fashion markNeedle loop of previous course and sinker loo

13、p of fashion course 12.4.1 Wale fashioning16 It involves the transfer of loops from one needle to another within the same needle bed, either transferring onto selvedge needles that are to start knitting (widening) or transferring from needles that are to cease knitting (narrowing). There is now an i

14、ncreasing number of automatic V-bed fiat machines with additional beds of fashioning points or rib loop transfer needles. 1712.4.2 The calculation of fashioning frequencies 成型工艺计算成型工艺计算 Fig.12.11 Full-fashioned shaping calculation181920 Shaping by three-dimensional wale fashioning occurs within the

15、width of needles, using an additional pair of independently-controlled fashioning boxes to shape stocking heels or bosom pouches. In the centre of the pouch, a number of needles knit plain fabric whilst on either side of them the extra sets of points widen outwards and later narrow again.12.4.3 Thre

16、e-dimensional wale fashioning2112.4.4 Needle selection shaping In needle selection shaping, the selvedge needle(s) is introduced or withdrawn from the knitting width by means of needle selection.1.By transferring and re-transferring rib loops in conjunction with needle bed racking2.By pressing-off l

17、oops, or3.By causing needles to hold their loops for large numbers of traverses 2212.4.5 Reciprocated knitting of pouches Three-dimensional shaping of pouches can be achieved on small-diameter hosiery machines by using held loop shaping in a similar manner to flat knitting, so that the number of cou

18、rses knitted by adjacent needles is varied in order to knit a pouch for a heel and, if necessary, for a toe. In the first half of the pouch-knitting sequence, only half the needles continue knitting, and during the reciprocating knitting, a needle at each edge is lowered out of action to join the in

19、step needles.2312.4.6 Shaping by changing the knitted stitch structure Stitch shaping is the imparting of shape into selvedged or tubular weft knitted structures by changing the nature of the stitch structure without altering the total number of needles that are in action. It may be used for garment-shaping sequences in knitwear, jerseywear and underwear produced on latch needle machines.242512.4.7 Shaping by altering the stitch lengthChanges of stitches length by alteration of stitch cam positions are carried out at particular points in a garment-length knitting sequence.The introduction o