Jacquard weaving
Encyclopedia
Jacquard weaving
Weaving
Weaving is a method of fabric production in which two distinct sets of yarns or threads are interlaced at right angles to form a fabric or cloth. The other methods are knitting, lace making and felting. The longitudinal threads are called the warp and the lateral threads are the weft or filling...

makes possible in almost any loom
Loom
A loom is a device used to weave cloth. The basic purpose of any loom is to hold the warp threads under tension to facilitate the interweaving of the weft threads...

 the programmed raising of each warp
Warp (weaving)
In weaving cloth, the warp is the set of lengthwise yarns that are held in tension on a frame or loom. The yarn that is inserted over-and-under the warp threads is called the weft, woof, or filler. Each individual warp thread in a fabric is called a warp end or end. Warp means "that which is thrown...

 thread independently of the others. This brings much greater versatility to the weaving
Weaving
Weaving is a method of fabric production in which two distinct sets of yarns or threads are interlaced at right angles to form a fabric or cloth. The other methods are knitting, lace making and felting. The longitudinal threads are called the warp and the lateral threads are the weft or filling...

 process, and offers the highest level of warp yarn control. 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.

History

In former times if figured designs were required, this was done on a drawloom. The heddle
Heddle
A heddle is an integral part of a loom. Each thread in the warp passes through a heddle, which is used to separate the warp threads for the passage of the weft. The typical heddle is made of cord or wire, and is suspended on a shaft of a loom. Each heddle has an eye in the center where the warp is...

s 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
Basile Bouchon
Basile Bouchon was a textile worker in the silk center in Lyon who invented a way to control a loom with a perforated paper tape in 1725. The son of an organ maker, Bouchon partially automated the tedious setting up process of the drawloom in which an operator lifted the warp threads using...

 introduced the principal 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.

The Jacquard process and the necessary loom attachment are named after their inventor, Joseph Marie Jacquard
Joseph Marie Jacquard
Joseph Marie Charles dit Jacquard played an important role in the development of the earliest programmable loom , which in turn played an important role in the development of other programmable machines, such as computers.- Early life :Jean Jacquard’s name was not really...

 (1752 - 1834). He 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, Jacquard himself designed. 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 perforted 'barrel'. Jacquard's machine also contained eight rows of needles and uprights as compared with Vaucanson's double row, 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 which was claimed for the Jacquard machine was that, previously in weaving damasks 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.

Jacquard's invention had a deep influence on Charles Babbage
Charles Babbage
Charles Babbage, FRS was an English mathematician, philosopher, inventor and mechanical engineer who originated the concept of a programmable computer...

. In that respect, he is viewed by some authors as a precursor of modern computing
Computing
Computing is usually defined as the activity of using and improving computer hardware and software. It is the computer-specific part of information technology...

 science.

Mechanical Jacquard looms

Originally the Jacquard machines were mechanical
Machine
A machine manages power to accomplish a task, examples include, a mechanical system, a computing system, an electronic system, and a molecular machine. In common usage, the meaning is that of a device having parts that perform or assist in performing any type of work...

, and the fabric design was stored in a series of punched card
Punched card
A punched card, punch card, IBM card, or Hollerith card is a piece of stiff paper that contains digital information represented by the presence or absence of holes in predefined positions...

s which were joined together to form a continuous chain. The Jacquards often were small and only independently controlled a relatively few warp ends. This required a number of repeats across the loom width. Larger capacity machines, or the use of multiple machines, allowed greater control, with fewer repeats, and hence larger designs to be woven across the loom width.

A factory
Factory
A factory or manufacturing plant is an industrial building where laborers manufacture goods or supervise machines processing one product into another. Most modern factories have large warehouses or warehouse-like facilities that contain heavy equipment used for assembly line production...

 must choose looms and shedding mechanisms to suit its commercial requirements. As a rule the more warp control required the greater the expense. So it is not economical to purchase Jacquard machines if one can make do with a dobby mechanism
Dobby loom
A Dobby Loom is a type of floor loom that controls the whole warp threads using a device called a dobby. Dobby is a corruption of "draw boy" which refers to the weaver's helpers who used to control the warp thread by pulling on draw threads....

. As well as the capital expense, the Jacquard machines are more costly to maintain, as they are complex and require higher skilled personnel; an expensive design system is required to prepare the designs for the loom, and possibly a card-cutting machine. Weaving is more costly since Jacquard mechanisms are more liable to produce faults than dobby or cam shedding. Also, the looms will not run as fast and down time will increase as it takes time to change the continuous chain of cards when a design changes. For these reasons it is best to weave larger batch sizes with mechanical Jacquards.

Electronic Jacquard looms

Bonas Machine Company Ltd. launched the first electronic Jacquard at ITMA, Milan
Milan
Milan is the second-largest city in Italy and the capital city of the region of Lombardy and of the province of Milan. The city proper has a population of about 1.3 million, while its urban area, roughly coinciding with its administrative province and the bordering Province of Monza and Brianza ,...

 in 1983. Although the machines were initially small, modern technology has allowed Jacquard machine capacity to increase significantly, and single end warp control can extend to more than 10,000 warp ends. This avoids the need for repeats and symmetrical designs and allows almost infinite versatility. The computer-controlled machines significantly reduce the down time associated with changing punched paper designs, thus allowing smaller batch sizes. However, electronic Jacquards are costly and may not be required in a factory weaving large batch sizes, and smaller designs. The larger machines allowing single end warp control are very expensive, and can only be justified where great versatility is required, or very specialized design requirements need to be met. For example, they are an ideal tool to increase the ability and stretch the versatility of the niche linen Jacquard weavers who remain active in Europe and the West, while most of the large batch commodity weaving has moved to low cost areas.

Linen
Linen
Linen is a textile made from the fibers of the flax plant, Linum usitatissimum. Linen is labor-intensive to manufacture, but when it is made into garments, it is valued for its exceptional coolness and freshness in hot weather....

 products associated with Jacquard weaving are linen damask napery, Jacquard apparel fabrics and damask bed linen.

Jacquard weaving of course uses all sorts of fibers and blends of fibers, and it is used in the production of fabrics for many end uses. Research is under way to develop layered and shaped items as reinforcing components for structures made from composite material
Composite material
Composite materials, often shortened to composites or called composition materials, are engineered or naturally occurring materials made from two or more constituent materials with significantly different physical or chemical properties which remain separate and distinct at the macroscopic or...

s.
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