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The Jacquard process and the necessary loom attachment are named after their inventor, Joseph Marie Jacquard (1752–1834). This mechanism is probably one of the most important weaving inventions as Jacquard shedding made possible the automatic production of unlimited varieties of pattern weaving. The term "Jacquard" is not specific or limited to any particular loom, but rather refers to the added control mechanism that automates the patterning. The process can also be used for patterned knitwear and machine-knitted textiles, such as jerseys. ==History== In former times, if figured designs were required, this was done on a drawloom. The heddles with warp ends to be pulled up were manually selected by a second operator (draw boy), apart from the weaver. It was slow and labour-intensive, with practical limitations on the complexity of the pattern. The first important improvement of the draw loom took place in 1725, when Basile Bouchon introduced the principle of applying a perforated band of paper. A continuous roll of paper was punched by hand, in sections, each of which represented one lash or tread, and the length of the roll was determined by the number of shots in each repeat of pattern. The Jacquard machine subsequently evolved from this. Joseph Marie Jacquard recognized that although weaving was intricate, it was repetitive, and saw that a mechanism could be developed for the production of sophisticated patterns just as it had been done for the production of simple patterns. It is difficult to determine what part of the 'Jacquard' machine was designed by Jacquard himself. He may have combined the best mechanical elements of other inventors, but - at any rate - the machine he made must have differed from its predecessors in arrangement and minor working details. It was similar in most general principles to Vaucanson's arrangement, except that he made use of Jean-Baptiste Falcon's individual paste board cards and his square prism (or card 'cylinder'), which he is credited with having fully perforated on each of its four sides in lieu of Vaucanson's perforated 'barrel'. Jacquard's machine also contained eight rows of needles and uprights as compared with Vaucanson's double row, of which modifications enabled him to increase the figuring capacity of the machine. In his first machine, he supported the harness by knotted cords, which he elevated by a single trap board. One of the chief advantages claimed for the Jacquard machine was that unlike previous damask-weaving machines, in which the figuring shed was usually drawn once for every four shots, with the new apparatus, it could be drawn on every shot, thus producing a fabric with greater definition of outline.〔Bradbury, Fred (1912). ''Jacquard Mechanisms and Harness Mounting''. John Heywood Ltd., Technical Book Depot, Halifax, Yorks.〕 Jacquard's invention had a deep influence on Charles Babbage. In that respect, he is viewed by some authors as a precursor of modern computing science.〔Essinger, James (2004). ''Jacquard's web''. Oxford University Press, Oxford. ISBN 978-0-19-280578-2〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Jacquard weaving」の詳細全文を読む スポンサード リンク
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