WELCOME TO OUR PRESENTATION
Presentation on: Chronological developments of loom
Presented to Presented by
Mr.Shamsuzzaman Sheikh Md. Anarul Islam (175042)
Assistant Professor Md. Sahab Uddin (175048)
Dept. of Textile Engineering, DUET Md. Imran Hossain (105050)
Md. Imam Hossain (175054)
Md. Mosaddekjaman (175056)
Md. Shamim Hossain (175059)
1
EVOLUTION OF WEAVING
2
THE HISTORY OF TEXTILE INDUSTRY IN
EGYPT
The textile industry is one of the oldest industries
worldwide as it has deep roots in history. It began with
Neanderthal man who realized the necessity for
something to cover and protect his body from the harsh
elements of nature. Egypt is considered a pioneer in the
textile industry as its history dates back thousands of
years(about 6000 years ago). Through the different
decades and with the support of different successive
governments, the textile industry has developed to
become a major pillar for the Egyptian development.
3
THE HISTORY OF TEXTILE INDUSTRY IN
CHINA
Chinese made fine fabrics from silk over 4000 years
ago. In the late 1800s, foreign imports from British
India of cotton yarn had created a large market for
weavers in the countryside of Northern China.
Foreign interests noticed several key benefits of
operating in China, including the vast market,
availability of cheap labor and raw materials, longer
work hours, and lower transport costs. The first
foreign enterprises were established immediately
after the Sino-Japanese War of 1904-05, within a
few years of the first Chinese factories.
4
HANDLOOM
Handloom refers to wooden frames of different types
which are used by skilled artisans to weave fabrics usually
from natural fibers like Cotton, Silk, Wool, Jute etc. It is a
cottage industry where the entire family is involved in the
production of cloth. Right from spinning the yarn,
coloring, to weaving on the loom if done by them. Fabric
produced from these looms is also referred to as
Handloom.
5
HISTORY OF HANDLOOM
1. In 12th century, completely wooden hand looms were used as standard designs in England.
2. The developments in the design and performance of looms have taken place during the past
850 years.
3. The fly shuttle, invented in 1733 by John Kay, was hand operated.
4. It was an important cornerstone to improve the productivity.
5. This shuttle, running on four wheels, was moving over the lower side of the warp sheet.
6. Two wooden tenders connected to a small cord commanded by the hand were used to propel
the shuttle. The weaver sitting in the middle of the loom threw the shuttle by pulling the cord
very easily.
6
DEVELOPMENTS IN POWER LOOM
7
INTRODUCTION
A power loom is a mechanized loom, and was one of the key
developments in the industrialization of weaving during the
early Industrial Revolution. By inventing this type looms-
Production rate becomes higher, need less labor worktime, mass
production becomes easier .
8
CONT.
• The first power loom was designed in 1784 by Edmund
Cartwright and first built in 1785. It was refined over the
next 47 years until a design by Kenworthy and Bullough
made the operation completely automatic.
• Traditional handlooms were slow and required several
laborers to operate. Cartwright’s invention of the power
loom was significant because it used mechanization to
automate much of the weaving process.
9
CONT.
• In early 1800s , looms made from cast iron were operated by
steam power
• After that in 1895, power loom driven by electric engine
were invented and used all over. The production is higher than
the previous power looms.
• At the beginning of 1930’s looms were driven by electric
motor. These looms were less noisy and less power
consumption than electric engine looms.
10
DEVELOPMENTS IN WEFT STOP MOTION
11
INTRODUCTION
Many problem arises when production runs. So there
need to stop loom for solving these problems. But if a
loom runs without knowing it, it can cause a great loss.
For this, automatic stop motion needs to apply on loom,
so that it can identify the defect, it stop the loom.
12
CONT.
• In 1976, automatic loom stopping motion was invented by R Miler. This
motion works when a short pick occurred.
• Advantages of automatic loom stop motion:
1. If any weft breaks, the loom will brake. For this no more weft will waste.
2. Prevents manufacturing of defected fabric
• But stopping production for some time is also a great loss. Later in 1894,
Northrop looms were marketed where automatic weft replacement can be
done without stopping the loom. It was fully automated power loom.
13
NEW TECHNOLOGY
Now some modern weft stop motion invented. They are:
• Piezoelectric electronic weft stop: In the case of rapier
and projectile weaving machine the mostly used device is
provided with piezoelectric crystals.
• The optical sensors: In the case of fluid Jet machines, it is
preferable not to hinder the weft fly, therefore optical sensors are
used which do not touch the weft.
14
CONT.
• Automation has resulted in control of machines electronically from user friendly
interfaces, produce intricate jacquard fabrics at the speed of commodity fabrics,
inspect fabrics on loom, use optical and laser detection of warp break, reduce
downtime due to higher levels of automation and quick style and warp beam change.
The machine speed upto 1000 rpm is possible, 5 to 10 times faster than 20 years ago.
15
WHY IS AUTOMATION IMPORTANT IN THE
WEAVING SECTOR?
• Global competition ensures that only the fittest survive. Today's weaver needs to
ensure that he/she is able to manufacture and supply the finest quality of fabric, at
the lowest cost, in the shortest possible time-frame. Automation is the only option
which will allow the weaver to attain this objective.
16
DEVELOPMENTS IN SHEDDING
MECHANISM
17
INTRODUCTION
• Earlier time, shedding mechanism was done by
tappet which had the capacity to produce a pattern /
weave is very much limited. A maximum of 8 or 10
tappets only can be used. Later some other
mechanism invented where the limitation reduces.
They are:
18
DOBBY SHEDDING
The first dobby operated by a punched card invented by
B.Bouchon in 1725. This is a compact, electronically
guided shedding motion and capable of having up to 48
shafts.. Design may be woven with two or more basic
weaves and their variation. Such fabrics may be referred as
dobby cloths or dobby weave, towels usually show
geometric designs when pattern is provided by dobby.
19
DOBBY SHEDDING
• Keighley Dobby : Design improved when Keighley
dobby was invented by Hattersley and Smith in
1867
• Rotary dobby: To achieve dobby shedding faster
speeds new generation dobby manufactured in 1900. It
can allow weaving machine speed up to 1000-1500
rpm.
20
ADVANTAGES OF DOBBY LOOM
• It can produce the more complex design.
• Theoretically, it can control maximum 48 heald frame but practically 36.
• For cotton yarn, it can control maximum 48 heald frame.
• Production is less than tappet.
21
JACQUARD SHEDDING
J.M. Jacquard constructed a machine controlling
bundles of harness cords with healds in 1801. To
provide with unlimited design width, jacquard
shedding is needed
Biggest weave is possible with jacquard shedding as
each warp yarn may be individually controlled.
22
ADVANTAGES OF JACQUARD SHEDDING
• -Jacquard shedding mechanisms are capable of producing large and intricate weave
designs that are beyond the scope of dobby shedding mechanisms.
• -In jacquard weaving, it is possible to control every warp yarn individually.
• -Many specialized types of jacquard machine have been developed for weaving
particular kinds of fabric, such as terry towels, damasks, and carpets.
• -Most of the rest are general purpose types that are comparatively easy to classify.
23
DEVELOPMENTS IN WEFT INSERTION
SYSTEM
24
INTRODUCTION
Weft insertion system is one of the major part in a loom’s
process. The production rate, capability, efficiency depends upon
it. In the past, weft insertion was done by hand, after that flying
shuttle uses in looms in 1733 by Jhon Kay, which makes the
insertion of weft into the shed easier.
Later weaving industry turns in a new path by improving the
weft insertion system. These make revolutionary change in
weaving industry. They newly weft insertion systems implement
in:
25
RAPIER LOOM
• In this weaving machine, weft insertion is done by rapier.
The development of the rapier loom began in 1844, when
John Smith of Salford was granted a patent on a loom
design that eliminated the shuttle typical of earlier models
of looms. In 1972, production of this machine started.
• This type of weaving is very versatile, in that rapier
looms can weave using a large variety of threads.
26
ADVANTAGES OF RAPIER:
The rapier loom can reach 12 colors, the shuttle loom can reach up to 6 colors
Rapier loom is too much perfect for weft patterning.
Fancy fabric is produced here.
loom speed of rapier loom varies from 200-260 ppm.
27
PROJECTILE LOOM
• The projectile(gripper)was first invented in 1924 by
Sulzer Brothers. After 29 years, in 1953, it
manufactured for commercial purpose. In this weaving
machine the weft insertion is carried out by small
clamp projectiles. There is no need of shuttle for weft
insertion through the shed. Maximum speeds on these
machines can be as high as 1,050 ppm.
28
ADVANTAGES OF PROJECTILE
 Projectile loom is less noisy than shuttle looms.
 Speed up to 600 ppm
 Lowest energy consumption
 Weaving cost is much lower than shuttle loom
29
AIR JET LOOM
• To insert weft in the shed, a jet of air can be used to
blow the weft yarn into the shed. The air-jet
loom was invented in 1914 but after 64 years, in 1980
it is commercially produced.
30
ADVANTAGES OF AIR JET
 The jet loom can reach up to 8 colors where the shuttle loom can reach up to 6 colors
 The big advantages of air jet looms, compared to shuttle weaving looms for example,
is that they are able to weave at a much faster rate.
 Weft insertion performance is too much here
 It consumes very low power
 They are able to achieve up to 1,500 picks per minute
31
WATER JET LOOM:
A water jet loom is similar to an air jet loom but
uses water instead of air to transport the yarn around
the shed. Water jet looms can weave very quickly
whilst the yarn is not damaged as water is less
abrasive than solid matter moving the yarn around
Water-jet looms use the same principle as air-jet
looms, but they take advantage of pressurized water
to propel the weft.. Picks per minute can reach as
high as 1,000
32
ADVANTAGES OF WATER JET
Water jet loom is up to 4 colors
This type of weaving is cheaper if water is available on the site
Yarn is less damaged cause of using water.
Production rate is higher up to 2000 ppm
This type of loom is suitable for synthetic fiber
33
MULTIPHASE WEAVING MACHINE
All the weaving techniques discussed thus far require that
the shed be open all the way across the machine for the
device carrying the filling yarns to pass through the shed.
This imposes a limit on loom speed. The
multiphase weaving machine overcomes this limitation
by forming many different sheds at different places
across the machine and forming these only as the weft
yarn inserted. In this way, a number of weft yarns can be
inserted, one behind the other
34
ADVANTAGES OF MULTIPHASE
• The production rate is higher than others
• More than one shed formed at a time
• Several phases of the working cycle take place at any instant time.
35
BOARD QUESTION
SOLVED
36
1. WRITE A SHORT NOTE ON THE CONSEQUENCES OF
POWER LOOM
What was it?
A loom is a device designed to weave threads into cloth. The power loom was a steam-powered loom that mechanized the
process, reducing the need for humans to oversee the weaving process. The original design was flawed, and needed
improvements.
How did it work?
Power looms worked very similarly to the original handlooms. With handlooms, foot pedals lifted and lowered the warp
(tightly strung threads) while the weft (weaker threads) were drawn in between the warp threads, creating cloth. Power
looms kept this basic process, but replaced the power source needed to draw the warp threads with steam power, reducing
the skill required to weave the cloth.
What was it for?
Quite simply, this innovation sped up the process of weaving cloth immensely, allowing for much more cloth to be
produced, and at a much faster rate.
37
CONT.
• How did people live before it?
Before the Industrial Revolution (which enabled the technology for the power loom),
weaving cloth for clothes was done by hand, usually a task done part-time by a
family of craftspeople.
• What was it for?
Quite simply, this innovation sped up the process of weaving cloth immensely,
allowing for much more cloth to be produced, and at a much faster rate.
38
2.WRITE A SHORT NOTE ON CONSEQUENCES
OF SHEDDING MECHANISM
Shedding is one of the 5 loom motions – The others are weft insertion, beat-up, take-up, and let-off
• Shedding separate the yarn sheet delivered from the weavers beam into two levels to form a space
(shed) to allow a pick of weft yarn to be inserted.
Which must required on shed
• Smallest possible : lowest possible additional warp tension • Clear enough : preventing faults • Proper
shed dwelling : convenient for weft Proper shed dwelling : convenient for weft insertion Smooth
movement of the heald frames.
39
CONT.
Four different types of shedding mechanisms are available for looms: –
Crank shedding mechanism (simplest)
– Tappet shedding mechanism
– Dobby shedding mechanism
– Jacquard shedding mechanism (most complex)
40
3. DISCUSS THE HISTORY OF WEFT INSERTION
SYSTEM
In conventional looms, shuttle was used as weft carrier to the shed. Then comes Rapier
loom.
In Rapier loom, weft insertion is done by rapier. The development of the rapier loom
began in 1844,.
Another loom called projectile(gripper)was first invented in 1924 by Sulzer Brothers.
In this weaving machine the weft insertion is carried out by small clamp projectiles.
There also comes jet loom which has high rate of weft insertion. In Air jet loom, a jet
of air can be used to blow the weft yarn into the shed. . The air-jet
loom was invented in 1914.Another jet loom is water jet loom. It uses water instead of
air to transport the yarn around the shed.
41
THANK YOU FOR YOUR ATTENTION
HAVE YOU ANY QUESTION?
42

Chronological developments of loom

  • 1.
    WELCOME TO OURPRESENTATION Presentation on: Chronological developments of loom Presented to Presented by Mr.Shamsuzzaman Sheikh Md. Anarul Islam (175042) Assistant Professor Md. Sahab Uddin (175048) Dept. of Textile Engineering, DUET Md. Imran Hossain (105050) Md. Imam Hossain (175054) Md. Mosaddekjaman (175056) Md. Shamim Hossain (175059) 1
  • 2.
  • 3.
    THE HISTORY OFTEXTILE INDUSTRY IN EGYPT The textile industry is one of the oldest industries worldwide as it has deep roots in history. It began with Neanderthal man who realized the necessity for something to cover and protect his body from the harsh elements of nature. Egypt is considered a pioneer in the textile industry as its history dates back thousands of years(about 6000 years ago). Through the different decades and with the support of different successive governments, the textile industry has developed to become a major pillar for the Egyptian development. 3
  • 4.
    THE HISTORY OFTEXTILE INDUSTRY IN CHINA Chinese made fine fabrics from silk over 4000 years ago. In the late 1800s, foreign imports from British India of cotton yarn had created a large market for weavers in the countryside of Northern China. Foreign interests noticed several key benefits of operating in China, including the vast market, availability of cheap labor and raw materials, longer work hours, and lower transport costs. The first foreign enterprises were established immediately after the Sino-Japanese War of 1904-05, within a few years of the first Chinese factories. 4
  • 5.
    HANDLOOM Handloom refers towooden frames of different types which are used by skilled artisans to weave fabrics usually from natural fibers like Cotton, Silk, Wool, Jute etc. It is a cottage industry where the entire family is involved in the production of cloth. Right from spinning the yarn, coloring, to weaving on the loom if done by them. Fabric produced from these looms is also referred to as Handloom. 5
  • 6.
    HISTORY OF HANDLOOM 1.In 12th century, completely wooden hand looms were used as standard designs in England. 2. The developments in the design and performance of looms have taken place during the past 850 years. 3. The fly shuttle, invented in 1733 by John Kay, was hand operated. 4. It was an important cornerstone to improve the productivity. 5. This shuttle, running on four wheels, was moving over the lower side of the warp sheet. 6. Two wooden tenders connected to a small cord commanded by the hand were used to propel the shuttle. The weaver sitting in the middle of the loom threw the shuttle by pulling the cord very easily. 6
  • 7.
  • 8.
    INTRODUCTION A power loomis a mechanized loom, and was one of the key developments in the industrialization of weaving during the early Industrial Revolution. By inventing this type looms- Production rate becomes higher, need less labor worktime, mass production becomes easier . 8
  • 9.
    CONT. • The firstpower loom was designed in 1784 by Edmund Cartwright and first built in 1785. It was refined over the next 47 years until a design by Kenworthy and Bullough made the operation completely automatic. • Traditional handlooms were slow and required several laborers to operate. Cartwright’s invention of the power loom was significant because it used mechanization to automate much of the weaving process. 9
  • 10.
    CONT. • In early1800s , looms made from cast iron were operated by steam power • After that in 1895, power loom driven by electric engine were invented and used all over. The production is higher than the previous power looms. • At the beginning of 1930’s looms were driven by electric motor. These looms were less noisy and less power consumption than electric engine looms. 10
  • 11.
    DEVELOPMENTS IN WEFTSTOP MOTION 11
  • 12.
    INTRODUCTION Many problem ariseswhen production runs. So there need to stop loom for solving these problems. But if a loom runs without knowing it, it can cause a great loss. For this, automatic stop motion needs to apply on loom, so that it can identify the defect, it stop the loom. 12
  • 13.
    CONT. • In 1976,automatic loom stopping motion was invented by R Miler. This motion works when a short pick occurred. • Advantages of automatic loom stop motion: 1. If any weft breaks, the loom will brake. For this no more weft will waste. 2. Prevents manufacturing of defected fabric • But stopping production for some time is also a great loss. Later in 1894, Northrop looms were marketed where automatic weft replacement can be done without stopping the loom. It was fully automated power loom. 13
  • 14.
    NEW TECHNOLOGY Now somemodern weft stop motion invented. They are: • Piezoelectric electronic weft stop: In the case of rapier and projectile weaving machine the mostly used device is provided with piezoelectric crystals. • The optical sensors: In the case of fluid Jet machines, it is preferable not to hinder the weft fly, therefore optical sensors are used which do not touch the weft. 14
  • 15.
    CONT. • Automation hasresulted in control of machines electronically from user friendly interfaces, produce intricate jacquard fabrics at the speed of commodity fabrics, inspect fabrics on loom, use optical and laser detection of warp break, reduce downtime due to higher levels of automation and quick style and warp beam change. The machine speed upto 1000 rpm is possible, 5 to 10 times faster than 20 years ago. 15
  • 16.
    WHY IS AUTOMATIONIMPORTANT IN THE WEAVING SECTOR? • Global competition ensures that only the fittest survive. Today's weaver needs to ensure that he/she is able to manufacture and supply the finest quality of fabric, at the lowest cost, in the shortest possible time-frame. Automation is the only option which will allow the weaver to attain this objective. 16
  • 17.
  • 18.
    INTRODUCTION • Earlier time,shedding mechanism was done by tappet which had the capacity to produce a pattern / weave is very much limited. A maximum of 8 or 10 tappets only can be used. Later some other mechanism invented where the limitation reduces. They are: 18
  • 19.
    DOBBY SHEDDING The firstdobby operated by a punched card invented by B.Bouchon in 1725. This is a compact, electronically guided shedding motion and capable of having up to 48 shafts.. Design may be woven with two or more basic weaves and their variation. Such fabrics may be referred as dobby cloths or dobby weave, towels usually show geometric designs when pattern is provided by dobby. 19
  • 20.
    DOBBY SHEDDING • KeighleyDobby : Design improved when Keighley dobby was invented by Hattersley and Smith in 1867 • Rotary dobby: To achieve dobby shedding faster speeds new generation dobby manufactured in 1900. It can allow weaving machine speed up to 1000-1500 rpm. 20
  • 21.
    ADVANTAGES OF DOBBYLOOM • It can produce the more complex design. • Theoretically, it can control maximum 48 heald frame but practically 36. • For cotton yarn, it can control maximum 48 heald frame. • Production is less than tappet. 21
  • 22.
    JACQUARD SHEDDING J.M. Jacquardconstructed a machine controlling bundles of harness cords with healds in 1801. To provide with unlimited design width, jacquard shedding is needed Biggest weave is possible with jacquard shedding as each warp yarn may be individually controlled. 22
  • 23.
    ADVANTAGES OF JACQUARDSHEDDING • -Jacquard shedding mechanisms are capable of producing large and intricate weave designs that are beyond the scope of dobby shedding mechanisms. • -In jacquard weaving, it is possible to control every warp yarn individually. • -Many specialized types of jacquard machine have been developed for weaving particular kinds of fabric, such as terry towels, damasks, and carpets. • -Most of the rest are general purpose types that are comparatively easy to classify. 23
  • 24.
    DEVELOPMENTS IN WEFTINSERTION SYSTEM 24
  • 25.
    INTRODUCTION Weft insertion systemis one of the major part in a loom’s process. The production rate, capability, efficiency depends upon it. In the past, weft insertion was done by hand, after that flying shuttle uses in looms in 1733 by Jhon Kay, which makes the insertion of weft into the shed easier. Later weaving industry turns in a new path by improving the weft insertion system. These make revolutionary change in weaving industry. They newly weft insertion systems implement in: 25
  • 26.
    RAPIER LOOM • Inthis weaving machine, weft insertion is done by rapier. The development of the rapier loom began in 1844, when John Smith of Salford was granted a patent on a loom design that eliminated the shuttle typical of earlier models of looms. In 1972, production of this machine started. • This type of weaving is very versatile, in that rapier looms can weave using a large variety of threads. 26
  • 27.
    ADVANTAGES OF RAPIER: Therapier loom can reach 12 colors, the shuttle loom can reach up to 6 colors Rapier loom is too much perfect for weft patterning. Fancy fabric is produced here. loom speed of rapier loom varies from 200-260 ppm. 27
  • 28.
    PROJECTILE LOOM • Theprojectile(gripper)was first invented in 1924 by Sulzer Brothers. After 29 years, in 1953, it manufactured for commercial purpose. In this weaving machine the weft insertion is carried out by small clamp projectiles. There is no need of shuttle for weft insertion through the shed. Maximum speeds on these machines can be as high as 1,050 ppm. 28
  • 29.
    ADVANTAGES OF PROJECTILE Projectile loom is less noisy than shuttle looms.  Speed up to 600 ppm  Lowest energy consumption  Weaving cost is much lower than shuttle loom 29
  • 30.
    AIR JET LOOM •To insert weft in the shed, a jet of air can be used to blow the weft yarn into the shed. The air-jet loom was invented in 1914 but after 64 years, in 1980 it is commercially produced. 30
  • 31.
    ADVANTAGES OF AIRJET  The jet loom can reach up to 8 colors where the shuttle loom can reach up to 6 colors  The big advantages of air jet looms, compared to shuttle weaving looms for example, is that they are able to weave at a much faster rate.  Weft insertion performance is too much here  It consumes very low power  They are able to achieve up to 1,500 picks per minute 31
  • 32.
    WATER JET LOOM: Awater jet loom is similar to an air jet loom but uses water instead of air to transport the yarn around the shed. Water jet looms can weave very quickly whilst the yarn is not damaged as water is less abrasive than solid matter moving the yarn around Water-jet looms use the same principle as air-jet looms, but they take advantage of pressurized water to propel the weft.. Picks per minute can reach as high as 1,000 32
  • 33.
    ADVANTAGES OF WATERJET Water jet loom is up to 4 colors This type of weaving is cheaper if water is available on the site Yarn is less damaged cause of using water. Production rate is higher up to 2000 ppm This type of loom is suitable for synthetic fiber 33
  • 34.
    MULTIPHASE WEAVING MACHINE Allthe weaving techniques discussed thus far require that the shed be open all the way across the machine for the device carrying the filling yarns to pass through the shed. This imposes a limit on loom speed. The multiphase weaving machine overcomes this limitation by forming many different sheds at different places across the machine and forming these only as the weft yarn inserted. In this way, a number of weft yarns can be inserted, one behind the other 34
  • 35.
    ADVANTAGES OF MULTIPHASE •The production rate is higher than others • More than one shed formed at a time • Several phases of the working cycle take place at any instant time. 35
  • 36.
  • 37.
    1. WRITE ASHORT NOTE ON THE CONSEQUENCES OF POWER LOOM What was it? A loom is a device designed to weave threads into cloth. The power loom was a steam-powered loom that mechanized the process, reducing the need for humans to oversee the weaving process. The original design was flawed, and needed improvements. How did it work? Power looms worked very similarly to the original handlooms. With handlooms, foot pedals lifted and lowered the warp (tightly strung threads) while the weft (weaker threads) were drawn in between the warp threads, creating cloth. Power looms kept this basic process, but replaced the power source needed to draw the warp threads with steam power, reducing the skill required to weave the cloth. What was it for? Quite simply, this innovation sped up the process of weaving cloth immensely, allowing for much more cloth to be produced, and at a much faster rate. 37
  • 38.
    CONT. • How didpeople live before it? Before the Industrial Revolution (which enabled the technology for the power loom), weaving cloth for clothes was done by hand, usually a task done part-time by a family of craftspeople. • What was it for? Quite simply, this innovation sped up the process of weaving cloth immensely, allowing for much more cloth to be produced, and at a much faster rate. 38
  • 39.
    2.WRITE A SHORTNOTE ON CONSEQUENCES OF SHEDDING MECHANISM Shedding is one of the 5 loom motions – The others are weft insertion, beat-up, take-up, and let-off • Shedding separate the yarn sheet delivered from the weavers beam into two levels to form a space (shed) to allow a pick of weft yarn to be inserted. Which must required on shed • Smallest possible : lowest possible additional warp tension • Clear enough : preventing faults • Proper shed dwelling : convenient for weft Proper shed dwelling : convenient for weft insertion Smooth movement of the heald frames. 39
  • 40.
    CONT. Four different typesof shedding mechanisms are available for looms: – Crank shedding mechanism (simplest) – Tappet shedding mechanism – Dobby shedding mechanism – Jacquard shedding mechanism (most complex) 40
  • 41.
    3. DISCUSS THEHISTORY OF WEFT INSERTION SYSTEM In conventional looms, shuttle was used as weft carrier to the shed. Then comes Rapier loom. In Rapier loom, weft insertion is done by rapier. The development of the rapier loom began in 1844,. Another loom called projectile(gripper)was first invented in 1924 by Sulzer Brothers. In this weaving machine the weft insertion is carried out by small clamp projectiles. There also comes jet loom which has high rate of weft insertion. In Air jet loom, a jet of air can be used to blow the weft yarn into the shed. . The air-jet loom was invented in 1914.Another jet loom is water jet loom. It uses water instead of air to transport the yarn around the shed. 41
  • 42.
    THANK YOU FORYOUR ATTENTION HAVE YOU ANY QUESTION? 42