Jacquard Technique

Whereas in the days before computers the patterns were read from punch cards, today the patterns are fed into the Jacquard machine directly from the computer. The information on whether the needle is supposed to pass, tuck, or knit is passed on directly to each needle. All three possibilities are combined in one cam part (Fig. 5.8). The needle foot can be moved out of the guiding channel in two places. In the position 1st selection, the needle can either remain in the position pass or move into tuck in the position 2nd selection, the needle can either remain in tuck or move into knit.  

Needle is in knit position Cam moves needle back into the circular movement position 

Presetting of pattern element by selection device Depending on pattern  

Expulsion of control foot by selection device Pattern sinker tilts sidewise 

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The electrodes are knitted on a first needle bed and then the base fabric is made on the second needle bed, which is opposed and facing the first one. The use of the well-known knitting technique intarsia allows the realization of an independent region with different threads without loose yams visible on the reverse side as with the Jacquard technique. In the case of intarsia, it has been possible to use for the same course two yam carriers one for the conductive thread and the other one for the nonconductive thread (Paradiso, 2004). 

Realization of the different pattern designs described above is done by using cam parts that are mounted into the cam box. A pattern change is therefore time consuming and expensive because cam parts have to be exchanged. In the Jacquard technique, the movement of each needle is controlled individually, hence allowing an almost limitless number of different patterns. Figure 5.7 shows a typical example. 

Figure 5.7 Pattern created using jacquard technique fabric appearance (left), detail (right)...

Figure 5.9 shows the different mechanisms in the Jacquard technique. Normally, the needle is in the knit position unless its sinker foot is expelled from the cam groove, which causes the needle to either tuck or pass. ... 

Increasing use of the Jacquard technique for the production of very fine circular knits. 

Jacquard looms 157 Jacquard technique 179 Jeans 86, 137, 166, 279 Jet loom 161 Jig 267... 

An article (Anon., 2002b) has reported on the possibility to produce cloth shoes with warp-knitted spacer fabrics on the Raschel machine. Prefabricated products and the application of various functional zones can be realized if the machines are equipped with a Jacquard pattern. The Jacquard pattern is a binding technique in which each warp thread is individually controlled allowing for a maximum range of production possibilities. The subsequent processing, for example, laminating, is easily possible. Examples are shown in Section 14.2.2. 

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