| 摘要 |
1,005,664. Designing woven fabrics; jacquards. LIPACO S.A. Dec. 8,1961 [Dec. 8, 1960], No. 43976/61. Headings D1E and D1K. Patterns are woven (from say black warp and white weft) by scanning an original in elementary areas equivalent to, say, 4 threads by 4 threads of the fabric, measuring the shade of each elementary area, and deriving control signals which not only produce the requisite number of warp lifts in the area to match the shade, but also so dispose the lifts in relation to those of adjacent areas that floats of excessive length are avoided. Since the areas occupy four picks of weaving, the signals are stored on magnetic tape and re-transmitted one pick at a time. Excessive floats are obviated by providing sixteen versions of each 4 x 4 weave, disposed as a 16 x 16 square. For example the lightest shade is obtained by a single warp thread lift in a 4 x 4 area; the 16 x 16 square consists of sixteen such 4 x 4 areas with the single lift placed in each of the possible sixteen positions; consequently in an area of any size woven at the lightest shade, no warp or weft thread can float over or under more than fifteen other threads. For darker shades, a greater number of warp lifts occur in the 4 x 4 areas, but each such arrangement of lifts includes the lifts employed for lighter shades in the samepart of the 16 x 16 area, thereby maintaining the condition for avoiding excessive floats. In order to reduce the amount of switching equipment, shades that required more than eight warp lifts in a 4 x 4 area are obtained by reversing the action of the switches that control lighter shades, so that the selected warp threads are left down and all the others are lifted instead. Jacquard: The lifting hooks of the jacquard are moved into and out of range of the griffe by pusher needles 301 slidable in bosses on a fixed frame 369 wound with individual coils 1C1. The coils are energized in succession by signals from the magnetic tape mentioned above to magnetise each needle in one direction of the other according to whether the associated warp thread is to be lifted or left down. When all the needles have been magnetised, a permanent magnet 376 approaches them and then recedes, taking with it those needles that are attracted by it and leaving behind those that are repelled.
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