Mechanical principle Looping process The yarns form a l […]
Mechanical principle
Looping process The yarns form a loop that becomes a knitted fabric through longitudinal stringing and lateral joining. So the loop is the basic process of knitting. The looping process can be broken down into the following stages in sequence: retreating - moving the newly formed coil (called the old coil) from the hook to the needle bar; the mating yarn - feeding the yarn onto the knitting needle; - bending the yarn into the shape of the coil; with the yarn - moving the yarn on the new mat or the coil that has just been bent into the hook; closing - closing the needle needle; ferrule - placing the old coil To the hook that the needle is closed.
The loop - the new yarn or the new coil meets the old coil inside and outside the hook; the loop - the old coil is removed from the hook and placed over the new coil; the loop - the yarn forms a closed sum A new coil of the specified size; pulling - pulling the new coil away from the looped area. This new coil becomes the old coil in the next cycle. There are two types of knitting processes and knitting methods. In the knitting process, the stages of the loop formation are carried out in the above order. During the braiding process, the yarn starts from the loop and is carried out simultaneously with the looping phase. In some knitting machines, each knitting needle sequentially completes the loop forming process in sequence; there are also some knitting machines in which the knitting process is performed simultaneously with each knitting needle.
Knitting production can be woven into various kinds of grey fabrics, cut and sewn into various knitwear, and the products can be directly woven on the machine to make fully formed or partially formed products. The forming process saves raw materials, simplifies or eliminates cutting and sewing processes, and improves product performance. Knitting production is rapidly developed due to short process, strong adaptability of raw materials, rapid change of varieties, wide range of products, low noise and low energy consumption. Since the 1970s, the productivity of knitting machines has been greatly improved. For example, a circular weft knitting machine (tongue needle) can weave about 3,000 stitches per minute. The warp knitting machine has a width of 427 cm, which is the highest per minute. Weaving 2000 coils, the speed of a single-cylinder sock machine can be up to 1000 rpm.
The use of electronic technology to control the work of the knitting machine increases machine efficiency. Various positive yarn feeders can be installed on the machine to improve product quality. Attaching some mechanism to the machine can weave knitted fabrics of various organizational structures and different uses: such as applying a needle selection mechanism to make the knitting needles work according to a pre-arranged procedure to weave jacquard knitted fabrics; applying a combing mechanism to feed the loose fibers into the weaving Needle to weave a plush knit fabric; apply a weft insertion device to weave the weft knitted fabric. There are more than 350 kinds of knitting machines. With the development of new chemical fiber varieties and finishing processes, the characteristics of the knitted fabrics such as scratching, ironing and abrasion resistance are improved. The application of finishing techniques such as brushing, sanding, shearing, ginning and pleating makes the variety of knitwear more extensive.