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National Institute of Fashion Institute, Kannur

Integrated Term ProjectOn

Dobby and Jacquard Loom

Submitted

byAditya Kumar

Shreya Sahu

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Acknowledgement

We would like to express our heartfelt gratitude to our mentor Mr. D Rajashekar

without whose support and proper guidance this Integrated Term Project would not

have been so.

We are also extremely thankful to Mr. Pari J, the

co-ordinator for making this endeavour possible. Without his proper guidance this

learning project would have not been fruitful.

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National Institute Of Fashion Technology, Kannur

CERTIFICATE

This is to certify that Integrated Term Project work entitled “Dobby and jacquard

Loom” is a bonafied work completed by Aditya Kumar and Shreya Sahu of

Semester-II, (B.FTech, Apparel Production) from the National Institute of Fashion

Technology, Kannur.

Mr. D Rajashekar Mr. Pari J

Associate Professor Co-ordinator, ITP

Mentor, B.FTech (A.P)

NIFT, Kannur NIFT, Kannur.

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INDEX

1. Introduction………………………………………………………06

2. Weaving…………………………………………………………. 07- 13i. Primary Motionii. Secondary Motioniii. Auxiliary Motion

3. Looms…………………………………………………………….14 – 21

4. Dobby Looms……………………………………………………22 - 28i. Introductionii. Shedding Mechanismiii. Types of dobbyiv. Advantages of dobby loomsv. Advancements in dobby looms

5. Jacquard Looms……………………………………………..…29 - 51i. Introductionii. Historyiii. Classification iv. Principle parts v. Mechanism connecting the engine to the loomvi. Conventional Mechanismvii. Functionviii. Problemsix. Advantages and Disadvantages of Jacquardx. Comparison between SLSC, DLSC and DLDC Jacquardsxi. Advancements in the Jacquard

6. Conclusion……………………………………………………..

7. Integration………………………………………………………

8. References……………………………………………………

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INTRODUCTION

Homo sapiens are believed to have first evolved about 200000 yrs ago. For almost all of this time, the new species clothed itself in skins and furs torn from the bodies of animals that had been slaughtered for food. The production of fabric which requires a considerable sophistication of civilization began, by comparison, far more recently. Earliest surviving fragments of cloth made of flax were found in Egypt dating 4500 BC. The production on a larger scale started with a major new invention – weaving. Then it was a simple process when rigid fibres such as reeds are being used. But rigid fibres do not make comfortable clothing. This needed to be produced from soft, flexible yarns. This lead to the invention of looms on which it can be achieved in a neat and convenient way. Loom is best defined as any frame or contrivance for holding warp threads parallel to permit the interlacing of the weft at right angles to form a web.

Myriads of appliances have been devised for the purpose of making the loom effective as the loom is the most necessary of the tools, the means of supplying one of the main indispensable needs of mankind-fabric. In consequence of the Industrial Revolution, the late 18th century had witnessed a considerable expansion in the automation of processes that had once been the preserve of small groups of highly skilled workers employed in so-called ‘cottage industries'. Moreover the need to add aesthetic patterns and designs to the fabric was also in demand.

This led to the evolution of Dobby and Jacquard loom. A Dobby Loom is a type of floor loom that controls the warp threads using a device called a dobby. Small, geometric figures can be woven in as a regular pattern on this loom. Most of the furnishing fabrics are woven by this method. But only simple designs were possible on this. Man was not satisfied and wanted to do elaborate designs on the fabric with the same independence that an artist enjoys while painting. This desire also got fulfilled with the invention of Jacquard loom.

Jacquard loom has no limitations on the type of design that can be automatically woven. It can be ‘programmed’ to create any desired design by using punch cards.

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In this system each individual warp can be lifted in a pre-planned sequence to produce a particular design on the fabric.

In addition to making various geometric as well intricate patterns and designs possible, these looms also helped weavers to get rid of normal draw looms which were maddeningly slow and tedious to use and made decorated fabrics affordable to a greater portion of the population. These lower prices are letting the average person be able to display these fine works in their homes and enjoy something once reserved for only the rich.

WEAVING

Weaving is the most ancient of the great arts, appearing at the dawn of history, virtually inseparable from the true culture. From the rough fish weirs to the most elaborate baskets, from the coarser fabrics of flax to the gossamer webs of cotton and silk, it has sustained and beautified man’s life from the night of history to the latest passing hour; It is the veritable nurse of civilization.

In general, weaving involves the interlacing of two sets of threads or yarns at right

angles to each other: the warp and the weft, to produce a two-dimensional fabric.

The warps are held taut and in parallel order, typically by means of a loom, though

some forms of weaving may use other methods. The loom is warped (or dressed)

with the warp threads passing through heddles on two or more harnesses. The warp

threads are moved up or down by the harnesses creating a space called the shed.

The weft thread is wound onto spools called bobbins. The bobbins are placed in a

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shuttle which carries the weft thread through the shed. The raising/lowering

sequence of warp threads gives rise to many possible weave structures from the

simplest plain weave (also called tabby), through twills and satins to complex

computer-generated interlacing. The cloth produced can be plain (in one color or a

simple pattern), or it can be woven in decorative or artistic designs, including

tapestries. The appearance of the fabric is determined by the uniformity of the of pick

spacing or the number of picks per inch of the cloth (ppi); the packing density of the

warp and weft in the body of the fabric or the fabric cover factor; the ratio of the warp

density to the weft density or the sett; the different color warp and weft used for

weaving, and the designs formed by changing the movement of the warp threads.

The productivity depends not only on the mechanization, but also on the quality of

the cloth and what kinds of design it has. Making complex designs on the fabric

lowers the productivity, but the resulting signs mark-up in the price of the fabric much

more than offsets the extra labor involved. With mechanisms such as the dobby and

jacquards, the productivity, depending on the complexity of the design, can go down

significantly, but the returns are very high.

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On the conventional loom, there are three basic motions that are carried out for

weaving a fabric. They are:

I. PRIMARY MOTIONS

The primary motion itself consists of three basic operations which form a continuous

cycle whether in the simplest hand loom or in the most complicated automatic

machine.

These primary motions are:

Shedding

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Picking

Beating up

In the absence of primary motions, Weaving is never possible.

1. SHEDDING

The raising and lowering of warp yarns is carried out by the heald frames that hold

the ends by means of heald and heals eyes. As the heald frames move up and down

an opening is formed between the ends called a SHED. This first weaving operation

is therefore known as shedding.

2. PICKING

Picking is the insertion of a weft thread across the warp yarns through the shed. On

raising the heald frames which in turn raises the warp yarns, the filling yarn is

inserted through the shed by a carrier device which is a shuttle. A shuttle with a weft

pirn is passed through the shed and as it passes a length of weft thread is unwound

from the weft pirn and it remains in the warp shed.

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3. BEAT UP

Beating up is basically carrying forward of the last inserted pick of weft to the cloth

already woven that is up to the cloth fell. All the warp yarns pass through the heald

eyelets and through openings in another frame that resembles a comb and is called

a reed. With each picking operation the reed automatically pushes or beats each

filling yarn against the fell of the cloth.This third essential weaving operation is

therefore called beating up, or battening. It gives the fabric a firm compact

construction.

The picking and beating up operations are fixed no matter what type of fabric is

being produced but the shedding motion is variable and can be described as the

heart of weaving as it is here that the nature of interlacing or the weave is decided.

II. SECONDARY MOTIONS

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The secondary motions consist of two operations:

Take up

Let off

In the absence of secondary motions, longer length of fabrics is not possible.

1. TAKE UP:

With each shedding picking and beating up operation the newly constructed fabric

must be wound on the cloth beam. This process is known as taking up.

The take up process involves pulling the cloth forward after the beat up of weft,

maintaining the same pick density and spacing throughout weaving of the cloth and

winding the woven cloth onto a roller. Thus, the take up motion determines the

speed of cloth withdrawal and therefore, the density of spacing of the weft picks in

the cloth.

2. LET OFF:

As the cloth is rolled up, the warp ends from the warp beam must be unwound so

that yarns will not be stretched to the point of breakage and the cloth fell position is

maintained at the desired point keeping the average warp tension constant. This

function is accomplished by the let off motion.

Thus the let off motion determines the rate at which the warp is fed forward and the

tension of the warp yarn. The tension is largely responsible for the configuration of

warp.

III. AUXILIARY MOTIONS

In order to produce good quality of cloth and to prevent damages it is necessary to

have some stop motions provided on the loom which are:

Warp stop motion

Weft fork stop motion

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Warp protector motion

Temples

Brakes

In the absence of auxiliary motions one can weave longer lengths of fabric but not

fault free fabric.

1. WARP STOP MOTION

The purpose of warp stop motion is to stop the loom when a warp thread breaks.

The loom also stops when a warp thread becomes excessively loose.

If a broken warp thread is not detected immediately it will tend t get entangled round

adjacent threads thus causing more end breakages or will create a fault known as

float in the woven cloth.

There are two types of warp stop motions:

Mechanical

Electrical

2. WEFT FORK STOP MOTION

This motion enables to stop the loom immediately after a weft break or weft running

out. In case the loom is allowed to run even after the weft breaks there will be no

woven cloth except long threads of warp.

There are two types of weft fork stop motions:

Side weft fork stop motion

Centre weft fork stop motion

3. WARP PROTECTOR MOTION

The function of the warp protector motion is to stop when the shuttle fails to reach

the shuttle fails to reach the shuttle box during picking.

There are two types:

Loose reed

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Fast reed

4. TEMPLES

In order to hold fast the width of the cloth as equal to as possible as possible to the

width of the warp of the reed, temples are provided near the fell of the cloth so as to

oppose the natural contraction taking place at the cloth fell.

Also the function of the temples is to prevent breakage at selvedge ends.

The types of temples are:

Full width temples

Nipper temples

Sun temples

Roller temples

Ring temples

Combination of different types

5. BRAKES

A brake is a device by means of which artificial frictional resistance is applied to a

moving body in order to stop the motion of a loom.

The most commonly used brakes in loom:

Shoe brake

Band brake

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LOOM

The word ‘loom’ is derived from the old English ‘geloma’ which means simply ‘tool’ or ‘utensil’.

A loom is a machine or device for weaving thread or yarn into textiles. In practice, the basic purpose of any loom is to hold the warp threads under tension to facilitate the interweaving of the weft threads. Loom is best defined generally as any frame or contrivance for holding warp threads parallel to permit the interlacing of the weft at right angles to form a web.

It is generally agreed that the weaving of textiles on looms began during the Neolithic Age in Europe. Vertical looms were probably the first to be invented. The earliest representation of a loom dated 5000 BC illustrates a horizontal ground loom from Badari. On this loom the warp is stretched horizontally between two beams pegged a few inches above the ground. The ancient Egyptians and Chinese used looms as early as 4000 BC. As long as the material to be woven was fairly rigid, no additional apparatus was necessary. How the loom developed was to a large extent dependent on what fiber was used for the warp. The history of the evolution of the loom is a history of minor innovations, mostly designed to increase the speed of fabric production.

The entire weaving process can be simplified into three basic operations- holding the warp under tension, opening and changing the shed, and inserting and beating up the weft. All the improvements and changes in loom design and construction are concerned with one or more of these problems. Once weaving entered the commercial arena, doing it better usually meant doing it faster. Today, pattern cards for Jacquard weaving can be cut by computer and woven at the rate of 200 picks per minute. On other modern looms water jets can propel weft yarn through a shed at the rate of 1000 picks per minute. The handloom, which began as a mechanism to furnish necessities, has survived as a specialized tool of the handicraftsman who furnishes art of luxury fabrics.

Looms can range from very small hand-held frames, to large free-standing hand looms, to huge automatic mechanical devices. The precise shape of the loom and its mechanics may vary, but the basic function is the same.

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Types of looms

On the basis of picking mechanism looms are divided into two types:

1. Shuttle looms

2. Shuttle less looms

1. Shuttle loom

It is the oldest and conventional type which uses a shuttle that contains a

bobbin of filling yarn. As the shuttle is batted/passed across the loom it leaves

a trial of filling at the rate of about 110 to 225 picks per minute.

Disadvantages

Shuttle sometimes causes abrasion on the warp yarns as it passes over them

and sometimes cause thread breakages

This in-turn results in machine stoppage in-order to tie the broken yarns

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It operates more slowly and are noisy

2. Shuttle-less Looms

It is developed to overcome the disadvantages in Shuttle looms. Each type

uses a different type of picking mechanism.

Projectile/Missie loom

It was developed in 1950’s in Switzerland. In this picking action is

accomplished by a series of small bullet-like projectiles which grip the filling

yarn and carry it through the shed and then return empty. All filling yarns are

inserted from same side of the loom. A special tucking device is used to hold

the ends of the filling to from the selvedge. Speed of 300 ppm can be

achieved on this loom. It is less noisy compared to shuttle loom.

Rapier Looms

It is competitors to missile loom. There are several types of this loom. One type uses

one long rapier device that reaches across the width of the loom to carry the filling

from one side to other side of the loom. Another type uses a double rapier, one on

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each side of the loom. Rapier construction may be of rigid, flexible etc. In each case,

one rapier feeds the filling yarn halfway through the shed to the arm on the other

side of the other rapier. It is more efficient. The speed ranges from 200 to 260 ppm.

Water-Jet Looms:It was first developed in Czechoslovakia in 1950’s and

subsequently refined by Japanese in the 1960’s. It is designed to weave faster

and to relieve the tension on the filling yarn as it is carried through the shed. A

pre-measured length of filling yarn is carried across the loom by a jet of water. It

operates at high speeds of about 600 ppm and noise levels are lower than

shuttle, missile and rapier. Disadvantage is that the water jet looms are restricted

to production of fabrics made of yarns that are not readily absorbent such as

filament yarns of acetate, nylon, polyester and glass. But it can produce superior

quality fabrics that have good appearance.

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Air-jet Looms

It was invented in Czechoslovakia and later refined by Swiss, Dutch and

Japanese. It is designed to retain the tensionless aspect of picking action of

water-jet while eliminating the problems caused by the use of water. It uses a jet

of air for insertion of filling yarns at the rate of about 600 ppm. It requires

uniformity in filling yarns and suitable for heavier yarns as the lighter yarns are

difficult to control through the shed.

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Circular Looms

It is specifically designed to produce tubular rather than flat fabrics. It requires shuttle device that circulates the filling in a shed formed around the machine. It used primarily for bagging material.

Other types include:

Handloom

The earliest looms were vertical shaft, with the heddles fixed in place in the shaft.

The warp threads pass alternately through a heddle and through a space between

the heddles, so that raising the shaft will raise half the threads (those passing

through the heddles), and lowering the shaft will lower the same threads -- the

threads passing through the spaces between the heddles remain in place.

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Haute lisse and basse lisse looms

Looms used for weaving traditional tapestry are classified as haute lisse looms,

where the warp is suspended vertically between two rolls, and the basse lisse looms,

where the warp extends horizontally between the rolls.

Power looms

The first completely automated loom was made by Jacques Vaucanson in 1745. It

was used for silk but didn't develop further. Edmund Cartwright built and patented a

power loom in 1785, and it was this that was adopted by the nascent cotton industry.

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Powered looms were shuttle-operated for two hundred years. In the early part of the

20th century the faster and more efficient shuttle less rapier looms and air looms

came into use. Modern industrial looms can weave at speeds 2000 Weft insertions

per minute. Today, advances in technology have produced a variety of looms

designed to maximize production for specific types of material. The most common of

these are air-jet looms and water-jet looms. Computer-driven looms are now also

available to individual (non-industrial) weavers.

Knitting looms

Knitting looms (also known as Amish looms or knitting boards) were recently

popularized in crafting circles by the Knifty Knitter system. Knitting looms are a

descendant of the frame loom. Grooved pegs are spaced along a central frame.

These pegs are wrapped with yarn in various ways, and then the knitter uses an

angled hook to pull the wrapped yarn over the top of the peg, resulting in a fabric

with stitches similar to a needle knitted item.

DOBBY LOOM

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INTRODUCTION

A Dobby Loom is a type of floor loom that controls the warp threads using a device

called a dobby. Dobby is short for "draw boy" which refers to the weaver's helpers

who used to control the warp thread by pulling on draw threads.

A dobby loom is an alternative to a treadle loom. Each of them is a floor loom in

which every warp thread on the loom is attached to a single shaft using a device

called a heddle. A shaft is sometimes known as a harness, but this terminology is

becoming obsolete among active weavers. Each shaft controls a set of threads.

Raising or lowering several shafts at the same time gives a huge variety of possible

sheds through which the shuttle containing the weft thread can be thrown.

A manual dobby uses a chain of bars or lags each of which has pegs inserted to

select the shafts to be moved. A computer assisted dobby loom uses a set of

solenoids or other electronic devices to select the shafts. Activation of these

solenoids is under the control of computer program. In either case the selected

shafts are raised or lowered by either leg power on a dobby pedal or electric or other

power sources.

On a treadle loom, each foot-operated treadle is connected by a linkage called a tie-

up to one or more shafts. More than one treadle can operate a single shaft. The tie-

up consists of cords or similar mechanical linkages tying the treadles to the lams that

actual lift or lowers the shaft.

On treadle operated looms, the number of sheds is limited by the number of treadles

available. An eight shaft loom can create 254 different sheds. There are actually 256

possibilities which is 2 to the power eight, but having all threads up or all threads

down isn't very useful. However, most eight shaft floor looms have only ten to twelve

treadles due to space limitations. This limits the weaver to ten to twelve distinct

sheds. It is possible to use both feet to get more sheds, but that is rarely done in

practice. It is even possible to change tie-ups in the middle of weaving a cloth but

this is a tedious and error prone process so this too is rarely done.

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With a dobby loom, all 254 possibilities are available at any time. This vastly

increases the number of cloth designs available to the weaver. The advantage of a

dobby loom becomes even more pronounced on looms with 12 shafts (4094 possible

sheds), 16 shafts (65,534 possible sheds), or more. It reaches its peak on a

Jacquard loom in which each thread is individually controlled.

A dobby can be employed in working forty-eight heald shafts. Each heald shaft has

its own pair of hooks, the front to the lift and the back one to depress.

Lags And Pegs

At the side of the dobby loom and touching the surface of the spring wires, is a

cylinder, carrying upon it a chain of flat wooden bars, named as lags. When in

working order, the lags are equipped with pegs which fill up certain holes, and

pressed against the spring wires, pushing the front hooks over the front knife and the

back hooks off the back knife. The exact order in which the lags are pressed does

not matter.

There are many forms of lag, and different methods of operating them; in some

power-loom dobbies, the lags are displaced by cards. Being chains, lags may be of

any length, containing one, two, three, or as many repeats of a pattern as may

appear advisable.

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DOBBY SHEDDING MECHANISM

In dobby shedding, the heald frames are operated by jacks and levers. The order of

lifting and lowering of the heald frames, as per a lifting plan, is controlled by a pattern

chain that gives unlimited scope for weaving designs, repeating on large number of

picks. This mechanism can control upto 24 heald frames, depending upon the crank

arm length.

The design possibilities are:

Twill

Satin

Crepe

Honeycomb

Huck-a-back

Mock leno

Bedford cord

Double cloth

The disadvantages of dobby mechanism are:

a. The mechanism is complicated

b. Initial cost is high

c. Maintenance cost is high

d. Can produce design faults in woven fabric

e. Tend to limit the loom speed when compared to the tappet shedding

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TYPES OF DOBBIES

Dobbies may be right-handed or left-handed, according to the position of the treadle

on the hand loom or the driving rod on the power loom. In pegging, it is necessary to

consider which hand the dobby belongs to, the rule being that the first lag which

turns in towards the dobby mechanism is the first to be pegged.

THE KEIGHLEY DOBBY

One of the most useful of the dobbies operated on the power loom is known as the

Keighley dobby. This dobby has been a great favourite with weavers of all classes of

fabrics. In this, the levers are dispensed within the lag mechanism, and the lags are

set directly to at upon the hooks.

A Dobby with Needles

In some particular dobbies, the lag cylinder suffers in comparison with the card

cylinder and the pegs do not obtain the same degree of favor as the needles.

Dobby with horizontal needle

The machine known as the single lift dobby stills finds its use. The frame is placed

over the centre of the loom, the ends of the vertical hooks being above the middle of

the shafts. Each hook passes through the eye of a horizontal needle; as this needle

is the means of lifting the hook on or off the griffe. All the needles are contained

within the framing, perforated plates at front and back holding them in position while

allowing them for free motion to and fro.

There are numerous dobby machines of various forms and applications. In all,

however, all the essentials are similar. Centre shed, double-lift, cross-border, the

Blackburn, the Burnley, the closed shed and positive open shed dobbies in their

several forms exhibit great ingenuity.

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ADVANTAGES OF DOBBY LOOMS

1. The ability to handle much longer sequences in the pattern. A weaver working

on a tread led loom must remember the entire sequence of tread lings that

make up the pattern, and must keep track of where they are in the sequence

at all times.

2. The dobby appliance is of immense service to textile manufacture. The

compactness of the machine, the wide range of heald-shafts it can control and

the directness of the relation between the pattern design and the heald shaft

mechanism are qualities which place dobby among the most useful of

shedding appliances.

3. On a manual dobby the sequence that makes up the pattern is represented by

the chain of dobby bars. The length of the sequence is limited by the length of

the dobby chain. This can easily be several hundred dobby bars, although an

average dobby chain will have approximately fifty bars.

4. A computer controlled dobby loom (Computer-Dobby) takes this one step

further by replacing the mechanical dobby chain with computer controlled

shaft selection.

5. In addition to being able to handle sequences that are virtually unlimited, the

construction of the shaft sequences is done on the computer screen rather

than by building a mechanical dobby chain. This allows the weaver to load

and switch weaves drafts in seconds without even getting up from the loom.

6. The design process performed on the computer provides the weaver with a

more intuitive way to design fabrics seeing it on the computer screen is easier

than trying to visualize it by looking at the dobby chain. One such example of

Computer-Dobby loom is Leclerc Weavebird Computer-Dobby looms.

7. Dobby looms expand a weaver’s capability and remove some of the tedious

work involved in designing and producing fabric. Many newer cloth design

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techniques such as network drafting can only reach their full potential on a

dobby loom.

ADVANCEMENTS IN DOBBY LOOMS

All shuttle looms can be modified in such a way that weft can be inserted

continuously without frequent pirn change. This method can be used in all types

of plain looms attached with dobby and also with drop box/under pick/pick and

pick mechanisms.

The dobby mechanism can be used to change the color of the weft as and when

required. A special mail eye is fitted in the dobby and they are lifted so that the

required color weft can be drawn from the particular mail eye.

With this system one can weave half of the fabric with one color, another half with

a different color by keeping two different color threads in both sides of the cones.

By providing more number of cones of different colors at the feeding end one can

weave stripe or check patterns without drop-box mechanism.

The advantages of this system are numerous:

3. For wider width looms this system is very much suitable. Small

sectors in the country can increase their production without any

extra expenditure.

4. Using this method one can weave fabrics like cotton, rayon,

polyester, silks using normal plain power looms.

5. The electronic warp stop motion and weft stop motion on these

looms give a fault free fabric.

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6. The system is less expensive and easy to maintain and saves time

in the production.

JACQUARD LOOM

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INTRODUCTION TO JACQUARD

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Decorated fabrics can only be woven by a loom that allows the raising and lowering of individual warp threads to permit the different coloured weft threads to be inserted by the shuttle in such a way that a design can be created in the fabric.

The first loom that made it possible to create a pattern in fabric was called a drawloom. The first draw loom was invented in China in or around the 2nd century BC. This loom allowed the warp threads to be drawn up individually to create a design to be woven. But it was maddeningly slow and search for a more user-friendly loom that could weave intricate designs only ended with invention of jacquard loom.

The Jacquard Loom is a mechanical loom, invented by Joseph Marie Jacquard. The Jacquard Loom is a mechanical loom, invented by Joseph Marie Jacquard in 1804, that simplifies the process of manufacturing textiles with complex patterns such as brocade, damask, and matelasse. The loom is controlled by punch cards with punched holes, each row of which corresponds to one row of the design. Multiple rows of holes are punched on each card and the many cards that compose the design of the textile are strung together in order. It is based on earlier inventions by the Frenchmen Basile Bouchon (1725), Jean Falcon (1728) and Jacques Vaucanson(1740).

On seeing Jacquard's punched card system, the mathematician Charles Babbage was inspired to use the same principles to design a mechanical calculating machine, the forerunner of modern computers, that he called the “Analytical Engine”. He himself wrote,

“The system of cards which Jacquard invented is means by which we can communicate to a very ordinary loom orders to weave any pattern that may be desired. Availing myself of the same beautiful invention I have by similar means communicated to my Calculating Engine orders to calculate any formula however complicated.”

200 years later, the inventions of Jacquard and Babbage led the world to the modern day computer which, among an almost infinite and growing number of uses, guides the jacquard loom in reproducing tapestries of exquisite detail.

HISTORY

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In consequence of the Industrial Revolution, the late 18th century had witnessed a

considerable expansion in the automation of processes that had once been the

preserve of small groups of highly skilled workers employed in so-called ‘cottage

industries'. The textile industry was one sphere were industrialization had rendered

obsolete such skills. Whereas, prior to the development of mechanical looms and

weaving machines, lengths of fabric had to be woven slowly by hand, the advent of

powered tools for carrying out this task meant that quantities of fabric could be mass-

produced at a far quicker rate than previously, thereby reducing its expense. There

was one area, however, where the new machines could not compete with skilled

manual workers, adding designs to fabric.

In 1804, however, everything changed. Jacquard unveiled the loom that now bears

his name. Joseph Marie Jacquard, a weaver of silk, invented the Jacquard loom,

which made use of punch cards in order to improve the functionality of the textile

loom. The Jacquard Loom provided a solution to this problem so that, with it in use,

extremely intricate patterns and pictures could be automatically woven into cloth at

much the same rate as a plain length of fabric could be generated. The jacquard

loom incorporated ideas from other, experimental looms, but in a way that created a

uniquely practical machine.

Like jacquard’s earlier loom, the jacquard loom could be operated without the help of

a draw boy, because a mechanical device that could lift the warp threads had been

added. Perhaps the most innovative feature of the jacquard loom, however, was that

it could be ‘programmed’ to create any desired design by using punch cards. A

punch card is a small card made of thick paper with a pattern of holes.

The punch- card system endowed the loom with flexibility; the punch cards could be arranged to create a repeating pattern or to weave one large design. Unlike Jacquard’s earlier loom, this loom had no limitations on the type of design that could be automatically woven. In addition, if a weaver wanted to use an identical design in other tapestry; the cards for that design could be reused. Since the jacquard loom

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lifted the correct threads automatically, the process of weaving designs became much faster. Earlier weaving designs into silk was an extremely time-consuming process and silk weavers often could not begin to meet the demand for the demand for their products. A skilled weaver and draw boy using the best equipment available used to produce only about an inch (2.54cm) of desired silk cloth a day. A weaver using a Jacquard loom could weave up to two feet (0.6m) of fabric each day, in any design imaginable, and all without the help of a draw boy. Jacquard’s loom astonished his contemporaries, and jacquard himself received enormous praise. In 1805, Napoleon decreed Jacquard’s loom public property, guaranteeing its inventor a lavish annual pension from the French government and a generous royalty for every jacquard loom brought into use.

Joseph Marie Jacquard's invention was fiercely opposed by the silk-weavers, who feared that its introduction, owing to the saving of labor, would deprive them of their livelihood. In fact, the introduction of these looms caused the riots against the replacement of people by machines in the second half of the 18th century.

However, its advantages secured its general adoption, and by 1812 there were 11,000 automated looms in use in France. The Jacquard loom was declared public property in 1806, and Jacquard was rewarded with a pension and a royalty on each machine. The looms allowed French weavers to make much larger, more elaborate designs than had been practical with previous looms. The result was a boon in the French textile industry and a sharp increase in demand for French fabrics abroad. France tried to maintain the advantage by keeping the new technology secret, but details of the Jacquard loom eventually leaked-out. By the 1830s, Jacquard looms were in use in other European countries, including Great Britain.

Jacquard continued making improvements to his loom. In 1819, he received the Cross of the Legion of Honour; one of France’s most prestigious awards. In the 1820s, Jacquard retired to the village of Oullins, where he died in 1834.

Jacquard looms are still in use, and the word jacquard is now a common noun meaning a fabric with an elaborate weave or pattern. Modern Jacquard looms are powered by electricity, and computers are used to develop the designs, but the basic process remains unchanged.

For inventing such a labor saving device, Joseph Jacquard should be applauded. His invention let weavers continue to make beautiful tapestries, but at a price that could be afforded by a greater portion of the population. These lower prices are letting the average person be able to display these fine works in their homes and enjoy something once reserved for only the rich.

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“The portrait of Jacquard was, in fact, a sheet of woven silk, framed and glazed, but looking so perfectly like an engraving that it has been mistaken for such by two members of the Royal Academy.”

Charles Babbage

The portrait deliberately designed to illustrate and show off the Jacquard loom’s capabilities, is so complex it contains 24000 rows of weaving. Every single row was controlled by a 19th century programming device – punching cards. These punched cards lie at the heart of Jacquard’s brilliant concept of an automatic loom that weaves complex patterns and images. The dimension of this is 20 x 14 inch. It is now preserved at Science Museum in London although unfortunately the portrait is no longer on general display.

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Jacquard introducing Napoleon to his newly-invented loom.

A Jacquard Loom workshop - Germany, 1858

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JACQUARD SHEDDING MECHANISM

A decorative woven or knitted pattern manufactured by using the Jacquard

attachment on the loom. This attachment has a punch card like a piano, so it offers

better design versatility and fabric control. In this shedding the warp ends are

controlled individually by harness cords. There will ne as many cords as there are

ends in the warp. There are no heald frames. Because the warp ends are controlled

individually by the shedding mechanism, the patterning possibilities are virtually

limited. Some types of jacquard fabrics have specific names, like damask and

brocade. Used in a variety of apparel, like our Holdup Suspenders and home goods

form drapes to upholstery.

The Jacquard Loom consists of two main parts:

1. Loom

2. Jacquard

The loom is bolted to the flooring and the jacquard is suspended from the ceiling

resting on heavy beams. The two are connected by a series of cords known as

Harness.

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PRINCIPLE PARTS OF THE JACQUARD MACHINE

A jacquard machine consists of three different parts:

(1) An engine i.e. shedding motion

(2) Harness, and

(3) A mechanism which connects the engine to the loom

ENGINE

This part of the machine contains the mechanism by which the warp threads are

selected and lifted to form the top shed line. Main parts of the engine are

Needles

Needle board

Spring box

Hooks

Griffe

Cylinder

Card Cradle

a. Needles

The needles rest with their heads in the needle-board, the needles extending outside

the needle board towards the cylinder by about 4 mm. The rear part of the needle - a

loop - passes in the spring-box. In a single lift jacquard, a needle carries at its rear

end small light helical spring contained in the spring-box. The needles are constantly

pushed towards the cylinder by these springs. If the needles are not pushed

backwards towards the spring-box, the upper crooks of the hooks will remain in the

position, over the griffe-bar and raising the latter will raise every one of these hooks;

but when the heads of the needles are pushed backwards, the hooks are also

moved out of the way of the rising griffe-bars, thus causing an empty lift when they

are raised.

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b. Needle-board

It is a wooden board perforated with holes corresponding to the number of needles

and it serves as a guide for the needles to be presented to the cylinder.

c. Spring- box

The rear part of the needle, a loop, is passed in the spring-box and the loop permits

a flat wire or a pin to be inserted which holds the needle in position. One pin is

required for each vertical row of the needles. A brass spiral spring is securely held

on one end by the wider part of the loop and on the other end by the pin inserted in

the loop. Pressing the needle at the head compresses the spring and removal of the

pressure at the head of the needle will bring the spring to its natural position, pushing

the needle to its original place.

d. Hooks

The vertical wires are turned over at the top to from a hook for which reason they are

called hooks of the jacquards machine. The top portion of the hook in its upright

position is over the griffe-bar or knife. As the hook passes through the bent portion of

the needle, it can be taken away from the knife if the needle is pressed back. The

hooks are doubled at the base and turned upwards for about one third of their

lengths. This double end is passed through a narrow slot in the grate. The end of the

double wire also forms a hook which normally rests on the semicircular ribs. The

double wire portion combined with the cross wire in the grate effectively prevents the

hook from twisting around. At the bottom portion of the double wire of the hook, short

but strong cords known as neck cords are looped and are subsequently passed

through the perforations of the tug board. Thus when a hook is raised a neck cord is

also lifted up along with it. In a single lift jacquard, there are as many hooks as the

number of hooks to that of the needles.

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e. Griffe

The knives are made of strong hoop iron and these horizontal knives (or griffe-bars)

are contained in the iron frame called the griffe on head. The griffe with the knives is

operated to rise and fall in a vertical plane. There are as many knives in a jacquard

as there are hooks in the short row. Every knife is fitted close to the hook but is

not allowed to press against them. The sides of the knives facing the hooks are

leveled off. This is to avoid the striking the top of the hooks are made to occupy

such a position that they will be caught by the knives, the hooks and

consequently the harness lines are lifted up when the griffe moves up.

f. Cylinder

The perforated cards are laced to form and endless chain over, a four sided

wooden prism called a cylinder. (Though called a cylinder, it is not circular in its

cross-section). It is made of very hard and well seasoned wood to prevent any

tendency to subsequent warping in the humid atmosphere of the weaving

department. Each face of the cylinder is perforated to correspond with the

number and arrangement of the needles in the machine. The tapering wooden

pegs are driven into every face, midway between the cylinder edges. These

pegs help in drawing forward and holding each card in turn, with its holes over

those in the cylinder.

The function of the card cylinder is to present on jacquard cards to the needles,

one at a time. A metal supporting end called lantern is fixed on each end of the

cylinder. The cylinder is supported by gudgeons, their bearings being in a frame

that moves horizontally. The cylinder is given two types of motions:

i. to-and fro motion

ii. rotary motion to the extent of one fourth revolution

Resting on the lantern of the cylinder is an inverted T-shaped hammer. A strong

spiral spring keeps the hammer in contact with the iron part of the cylinder.

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g. Card Cradle

When a large number of cards are to be worked on the machine, the entire

weight of the cards will have to be borne by the Jacquard machine. A long

endless chain of cards suspended above will also obstruct the working and

vision of the loom parts. It is also necessary to keep the bulk of the cards in a

convenient position so that they may be taken up by the cylinder in a proper

sequence. In order to achieve all these functions, a card-cradle is provided

below the iron on steel girders on which the jacquard machine is mounted.

Wires, slightly longer than the length of the cards are attached to the set of cards

at regular intervals of say 12, 16, 20 or 24 cards. A card cradle consists of two

curved iron rods kept at a distance slightly in excess of the length of the cards.

When the attached wire reaches these curved rods, its ends rest on them

thereby supporting the cards.

MECHANISM WHICH CONNECTS THE ENGINE TO THE LOOM

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A jacquard is installed on a support over the loom in many ways. The support is

known as gantry. It is made of steel or wooden beams carried on columns resting on

the ground or hung from the ceiling. The best height for a jacquard is generally

decided by the width of the warp in the reed.

Jacquard is usually driven from the loom shaft by means of rods and levers. Modern

driving motions are either by steel roller chains with machine cut wheels or by a

vertical revolving shaft with a bevel and bevel wheel drive.

In jacquard shedding two drives are essential:

(1) To drive the griffe in a vertical plane so as to operate the hooks and

(2) To drive the cylinder.

The cylinder in its turn needs two types of drives:

a. Cylinder with its cards facing the needle board should move towards the

needles to accomplish the selection is over, the cylinder should move away from the

needle board so that it should be turned through a quarter turn to present another

card when it moves into the needle board next time. This is to-and-fro motion of the

cylinder.

b. When the cylinder moves out, it should get a quarter turn, as mentioned

above to present the next card in the series. This is a rotary motion of the cylinder.

There are many ways in which the above motions and drives are obtained which

one can easily study on machine with which he has to work.

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CONVENTIONAL MECHANISMS

Jacquards are devices that help form the warp shed in the desired manner. They

consist of two parts, namely a selection device for choosing which warp threads are

to go up and which are to remain down, a lifting mechanism to lift the warp that has

to be raised.

Lifting mechanism

Warp pass through the eyes in the heald cords instead of the heald wires as in the

case of frame shedding. Warp threads are divided into groups that are connected to

hooks resting above them by a system of harnesses that are guided by the comber

board. The knives constantly move up and down and lift the hooks that are resting

on them. If a particular hook is required to stay down, (i.e. the warp threads are

supposed to stay down), then it is made to disengage from the knife. When the knife

goes up, tile selected hook stays down while the others go up.

Selection device

The selection of the hook is done by a mechanism that is preprogrammed to control

the hooks according to the design. The design program is in the form of a card in

which holes have been punched. Each card represents an individual pick while each

hole on the card (or the space where tile hole could be but is not) controls an

individual group of ends. A chain of cards, with holes punched in them, is used as

required. The number of cards in the chain is equal to tile number of picks in the

length of the repeat of the design along the warp. The chain of cards moves on a

quadrangular cylinder that rotates to present a new card to the needles after every

pick. The needles are perpendicular to the hooks and loop around them. When a

needle moves horizontally, the hook catches in the loop and bends away from the

knife. The needles are arranged in such a way that they are aligned with holes (or

the places where the holes could have been) in the card. The cylinder on which the

chain of cards moves can also oscillate horizontally back and forth. This is done to

facilitate the rotational movement of the cylinder.

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FUNCTION

Most of the fabrics are used for domestic and industrial purposes, but some of the

fabrics have decorative uses. A fabric may be ornamented by:

Embroidering

Printing

Figured weaving

In the first two cases the fabric is first manufactured and ornamentation is done

subsequently but in the case of figured weaving the cloth is ornamented

simultaneously with its production. Dobbies and jacquard shedding are employed.

The expression jacquard loom which is frequently used is a misnomer since the term

jacquard implies to shedding mechanism only which can be mounted on any loom by

making a few alterations. There is no heald-shaft harness as used in dobby or tappet

shedding mechanism but instead a thread harness is used.

Jacquard weave is used to produce patterned fabrics. The intricate patterns or figures are created all over the fabrics. Fabrics of jacquard weave are costly because it involves more time and skill in making the Jacquard cards to produce new pattern. Moreover the weaving operation is also very slow.

Characteristics of Jacquard Weave The fabrics have the tendency to have floats. It has luster contrasts.

It has snagging potential.

It is more stable and resilient than the basic weaves.

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All fancy or figured fabrics such as

Silk

Cotton brocades

Damasks

Brocatelle

Matelasse

Toilet quilts

Extra-warp or extra-welt figured fabrics

Figured equal or unequal double cloths

Madras muslin

Swivel fabrics

Leno brocades

Tapestries

Portraits

Animals

Geometrical figures

Landscapes

The above fabrics require the jacquard shedding mechanism to weave them on the

loom. A number of weaves may be used in combination to produce a Jacquard

design with the desired effects. Jacquard weaving is, however, an expensive form of

weaving as it is accompanied with designing, card cutting, lacing and all other jobs

associated with. The speed of the loom with jacquard shedding mechanism is also

lower than that of a similar loom with dobby or tappet shedding.

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CLASSIFICATION OF JACQUARD

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The Ordinary Mechanical Jacquard can be classified on three basis, viz:

I. Types of shed:

1. Bottom closed shed

2. Centre closed shed

3. Open shed

4. Semi-open shed

II. Number of griffe:

1. Single-

a. Single lift single cylinder

2. Double-

a. Double lift single cylinder

b. Double lift double cylinder

III. Pitch:

The Special Mechanical Jacquards are of many types. Some of them are:

Cross-border Jacquard

Self-twilling Jacquard

Plain Double Cloth Jacquard

Leno Jacquard

Split Harness Jacquard

Pressure Harness Jacquard

Marseilles Quilt Harness Jacquard

Mitchelline Quilt Harness Jacquard

The Electronic Jacquards are of three kinds; viz:

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1. Grossee

2. Bonus

3. Staubli

Comparison Between Slsc, Dlsc And Dldc

BASIS SLSC DLSC DLDC

No. Of lifting agents

There is a single lifting agents

There are two lifting agents

There are two lifting agents

No. Of cylinders

There is a single cylinder.

There is a single cylinder.

There are two cylinders.

Ends controlled by

Each end is controlled by single hook.

Each end is controlled by two hooks.

Each end is controlled by to hooks.

Type of shed

Bottom closed shed is formed

Semi open shed is formed

Semi open shed is formed

Drive to griffe

Drive to griffe from crank shaft

Drive to griffe from bottom shaft

Drive to griffe from crank shaft with the help of common shaft

BASIS SLSC DLSC DLDC

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Drive to cylinder

Drive to cylinder from crank shaft

Drive to cylinder from crank shaft

Drive to cylinder from crank shaft with the help of a common shaft

Beating up

Beating up is done in closed shed so firm beat up is not possible.

Beating up is done in crossed shed so firm beat up is possible.

Beating up is done in cross shed so firm beat up is possible.

Use

Usually used in delicate weaving

Used in ordinary weaving forms of cotton weaving

Used in cotton and heavy weaving industry

SLSC-Single lift single cylinder

DLSC-Double lift single cylinder

DLDC-Double lift double cylinder

JACQUARD WEAVING IN INDIA

The Jacquard loom was introduced in India under the British and soon became the preferred choice of weavers as they could create complex designs with much less labour. It also reduced the cost of cloth and brought it within the reach of the lower classes. Today, the Jacquard loom is used in various parts of India. The main centres are Delhi, Jaipur, Varanasi, Kanchi, Kolkata, and Mangalore where cloth for products like tapestry, upholstery, saris, shawls, scarves and other apparels are produced.

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PROBLEMS

1. Effort

When the warp warps are in their natural position, that is, in a straight line between

the warp beam and the cloth roller, they are said to be in the centre shed position.

When they have moved to the top position they are said to be in the top shed and

when they are in the bottom position they are said to be in bottom shed.

In the centre shed the warp are in the least motion. Because they are distorted out of

their straight line in both the top and the bottom shed, the tension in the warp

increases with a tendency for them to revert to the centre shed.

In a jacquard the normal position for a warp is the bottom shed. The warps are

normally distorted in the bottom shed position. When a shed is formed, the warps

that are supposed to be above during that pick go up while the other warps remain

down. This means that a jacquard is a negative mechanism, that is, it can move the

warps in just one direction. It can only raise the threads which then come down

owing to gravity.

Because the warps in the normal bottom shed are distorted out of shape, the tension

in them tries to pull them up. It is very important for them to remain in a clean bottom

shed line. If the warps are not at the same level, the shuttle flying over them will get

caught in them and break them. To keep the warp threads down in the bottom shed,

a downward force has to be applied to keep them down. In existing jacquards this is

done with the help of lingoes which are lengths of wires with a specific weight. These

lingoes hang from the eye harness, keeping the warp in the bottom shed position.

With the warp groups, the corresponding lingoes also have to be lifted up. The

weight of these lingoes adds up, as usually a couple of thousand odd threads are

worked upon. For example, if 2000 warps are being used and 12 grams of lingoes

are hanging from each eye harness and if half of the warps have to go up (as in the

case of a plain weave), then a dead weight of 12 kg has to be lifted. The problem is

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severe in case of very complicated designs when weights close to 40-50 kg need to

be lifted.

2. Height

The conventional jacquards are very tall mechanisms for which either a special work

shed is required or weaving is done in the open.

This problem occurs because of the geometry of the harness that connects the

hooks to the heald cords, with the warp running through their corresponding eyes.

The warp threads that are not directly below the hook, to which they are attached,

rise up less than the one that is directly below. In fact the warp threads further away

from the one directly below the hook, rise successively less and less. The problem

becomes very pronounced in jacquards of big widths. The shed opening towards the

side ends of the loom gets progressively smaller and results in the shuttle rubbing on

the thread.

The height of a conventional jacquard is dependent on the harness which has to be

long in order to minimize this problem.

3. Complexity and cost

The existing jacquards are very heavy and complicated mechanisms. The selection

device does not directly act on the hooks, but through an interface, that is the

needless.

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ADVANTAGES AND DISADVANTAGES OF JACQUARD LOOM

ADVANTAGES

1. Can produce fabrics up to 600 epi or ppi.

2. Helps in constructing intricate design which are otherwise impossible by

dobby and tappet shedding mechanisms

3. Due to presence of cards, weaving of complex designs becomes possible. It is

a more simple method of feeding the design to the loom to weave.

4. Have lingoes for maintaining tension in the warp threads

5. Possible to control every warp yarn individually

6. As there are different cylinders for even and odd picks, each cylinder has to

turn one quarter in every two picks.

7. With the help of the casting out process, it is desirable to omit whole rows of

hooks if not required. This simplifies the designing and card-cutting process.

DISADVANTAGES

1. This mechanism contains more moving parts

2. Initial cost is very high

3. Maintenance cost is also high

4. Can produce design faults in fabric

5. Preparing a design and cutting pattern cards requires skilled labor

6. Limitations on the speed of the loom due to complex mechanism

7. The loom becomes very large

8. There is a lot of wear and tear of the parts: hooks, needles, springs

9. Generates semi-open shed, in which there is unnecessary movement of warp

threads to the bottom shed line

10. Less efficient as manual operation

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11. The link transfer between the hooks occurs at the highest speed of these

hooks, this result in the jerky performance of the harness cords which may result in

‘lashing’.

Advancements In Jacquard Looms

Since it takes a long time to produce a point-paper design (approx. two

hundred hours for one design), the computer can scan the pattern very rapidly and,

by means of a program, convert the warp and filling interlacing into a binary number

form that can be ‘read’ by the computer. The changes in the design can be made by

using light sonic pen.

The advantages of this system over regular jacquard looms are:

Computer systems may be too expensive; however, automation shortens the

lead time between the design concept and the production of a sample.

More than one version of a design can be made so there is more opportunity

for experimentation in the designing process.

Fast sampling may be economical because styling approval can be given

quickly.

Manual card cutting is eliminated, for sampling as well as for large-scale

production.

No need for special personnel training and thus, paying competitive wages for

jacquard card cutting.

The magnetic tape required for making the final design can be stored in the

computer for future use.

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REFERENCES

WEBSITES:

www.texmin.nic.in www.indiantextilejournal.com www.indianmba.com www.baharttextile.com www.fabric-manufacturers.com www.ecvv.com www.housefabric.com

BOOKS:

Handbook of Cotton Weaving, by M.I.R. Publishers

Mechanism of Weaving, by Thomas. W. Fox

Fancy Weaving Mechanisms

Handbook of Weaving: Jacquard, by Puneet Kishore

Principles of Weaving, by K.T. Ashwani

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