Knitting is the second most important method used in fabric construction. In 1589, Rever and William Lee, English men invented the first knitting machine. Today the modern machine is based onthe same general principles estabilished by William Lee. Knitting is the construction of the fabric by forming the yarn into loops which hang upon the other. This fabric may be constructed by a single yarn or by a group of yarns running lengthwise. Another definition of knitting is as follows-Knitting is a cloth of interlocking loops from one or more yarns or from a series of yarns.
The construction of a knitted fabric is evaluated by the number of stitches or loops that can be counted in any square inch. This vertical rows of loops stitches in the knit fabric are known as wales and the horizontal rows of loops are known as courses. Knitted loops are usually referred to as stitches when they are pulled through another loop. The number of stitches in warp and weft direction, in a square inch of knitted fabric is referred to as count. The fineness of the fabric given by the number of stitches/needles per unit width on the machine is Gauge. The higher the gauge number the finer the fabric willl be.
The number of slots or grooves per inch in any given knitting machine is fixed; different machines have different quantities of slots. This number is called the cut of the machine. The size of the loop and the fineness of the yarn determine the density of course and wales. The number of wales determine the width of the fabric, the number of courses determine its length; their product determines the weight.
Machine knitting consists of forming loops of yarn with the aid of the thin pointed needles or shafts. As new loops are formed they are drawn through those previously shaped. This interlooping produces knit fabric. Knitting requires four basic components; (a) Yarn source, (b) Knitting elements, (c) Fabric take down and (d) Fabric collection.
a. Yarn source:
The yarn source for weft knitting may be located above the knitting area or on large creels at the side. If at the sides, the yarns are carried to the top of the knitting machine and then fed down to the knitting area.
b. Knitting elements:
Actual knitting elements include needles, the sinkers, needle bed or frame and the yarn carriers.
c. Fabric take down:
It is a device to pull the formed fabric towards the base of the machine.
d. Fabric collection:
A roll of some kind on which the completed fabric is collected.