Singlecylinder Machines

From a technical point of view, these machines should be classified as single-bed machines since they incorporate only one series of needles assembled in a cylindrical needle-bed and a series of sinkers which operate, together with the needles, during the stitch formation process. The selection is carried out by means of sliders and the movements are transmitted to the stitch formation motions by means of cams.

A special motion called "dial" is assembled above the cylinder; the dial integrates special hooks which operate during the formation of the double welt and the automatic closing of toe.

Picture 119 - Knitting head of a single-cylinder machine with the needles in the dial

These machines are available in fine gauges for the manufacturing of women's fine stockings and tights, as well as in coarse gauges for the manufacturing of sports and men's socks. The most recent technological trend aims to standardise the models of all manufacturers, i.e. manufacture fully electronic machines and simplify the machine by reducing the number of feed systems, making it faster and more cost-effective.

The basic technical features of these machines are: 4 to 6-inch diameter, 4 to 6 feed systems, completely electronic needle-by-needle selection by means of 16-level actuators, possibility of knitting heel and toe with a reciprocating motion, speed up to 1,000 rpm for simple patterns and 500 rpm for more complicated patterns.

Hosiery items can be manufactured in two different ways: the traditional cycle is based on full-fashioned heel and toe: in this case, when knitting the heel and the toe, only some needles operate along with one or two feed systems, and the cylinder rotates with a reciprocating motion.

The machines operating this way usually incorporate 4 feed systems, generally the first one works during the formation of the leg and the foot and when knitting the full-fashioned heel and toe, and has a larger number of thread guides (up to 7) while the other feed systems only work during the leg and foot formation and have less thread-guides (up to 5).

An alternative solution to this knitting technique is "tubular" knitting, i.e. the manufacturing of hosiery without toe or heel. Thanks to this process the toe is originally open and sewn at a later stage; on modern machines, the toe can be also sewn automatically during the production process. These machines are less complicated from a mechanical point of view and allow a higher throughput speed over the whole knitting cycle. However, the quality of hosiery produced on these machines is poorer if compared to the quality of articles with full-fashioned heel and toe.

On many single-cylinder models the number of colours of the pattern designs are strictly related to the number of feed systems assembled on the machine; several machine models can also carry out terry stitches.

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