BGMEA University of Fashion &
Technology (BUFT)
Course Code: TEX3104
Course Title: Fabric Manufacturing Engineering-II (lab)
Lab Report Submission
Submitted To
Ms. Taslima Ahmed Tamanna
Lecturer, Dept. of TE
BGMEA University of Fashion & Technology (BUFT)

Group No. Name ID Image
191, TE-
2B
G- 04
Shiblee Hossain Rifat 191-091-801
T. M. Ashikur Rahman 191-097-801
Md. Najmus Shakib 191-098-801
Md. Ariful Islam 191-099-8s01
Mahamudur Rahman 191-100-801

No. Experiment Name Page No.
1. Study on Basic structure of a Loom/ Weaving machine. 4-10
1.1 Study on tappet shedding mechanism. 11-17
2. Study on Dobby shedding mechanism. 18-28
3. Study on picking mechanism of a shuttle loom. 29-44
4. Study on beat-up mechanism. 45-52
5. Study on Take-up mechanism of a weaving machine/Loom. 53-62
6. Study on Let off Mechanism. 63-68
7. Study on cam setting process of circular knitting machine. 69-83
8. Study on V-bed Knitting Machine. 84-91
9. Study on different parts with function and working principle of
Warp knitting m/c.
92-98
10. Study on pattern mechanism of warp knitting machine. 99-102
INDEX

BGMEA University of Fashion and
Technology (BUFT)
Experiment No: 01
Experiment Name: Study on Basic structure of a Loom/Weaving machine.
Group: 04 Sec-2B
Lab Report
Submitted to: Submitted by:
Ms. Taslima Ahmed Tamanna Id. 191-091-801
Lecturer, BUFT 191-097-801
Department of TE 191-098-801
191-099-801
Date: 12-04-2021 191-100-801

01
Study on Basic structure of a Loom/ Weaving machine.
Introduction:
A loom is a device used to weave cloth and tapestry. Loom is a machine which used to
manufacture woven fabric. The basic purpose of any loom is to hold the warp threads under
tension to facilitate the interweaving of the weft threads. The precise shape of the loom and its
mechanics may vary, but the basic function is the same. Loom are driven by two ways. These are
manual system and automatic system.
Objectives:
1. To know about basic structure of a Loom/ Weaving machine
2. To know about how to produce fabric by loom without any damage.
3. To know about different parts of a loom and their functions.
4. To know about different motions which are used in loom.
Apparatus:
1. Loom/ Weaving machine
2. Weft yarn
3. Warp yarn
4. Cloth beam
5. Weaver’s beam
6. Shuttle
Description:
The process of producing a fabric by interlacing warp and weft threads is known as weaving. The
machine used for weaving is known as weaving machine or loom. The basic purpose of any loom
is to hold the warp threads under tension to facilitate the interweaving of the weft threads.
Shedding, picking, beat up. In the loom, yarn processing includes shedding, picking, battening
and taking-up operations. A weaving loom forms yarns into fabric by controlling the warp let-off
and fabric take-up, the patterning of the yarns, the insertion of the filling or picks, and the
beating-up of the filling yarn into the fabric. A loom contains different parts. Every part has
individual function. The major components of the loom are the warp beam, heddles, harnesses
or shafts, shuttle, reed and take up roll. The precise shape of the loom and its mechanics may
vary, but the basic function is the same. Warp yarns are held taut within the loom, and weft yarns
are inserted and pushed into place to make the fabric. The conversion of warp sheet into fabric
by interlacing with weft yarn requires the basic operations to be carried out on loom in a specific

order. It involves the primary motions, secondary motions and the stop motions. Loom motion
controls the fabric production.
Image of a loom:

Different parts & function of loom during weaving:
• Warp Beam
• Healds Shaft
• Shuttle
• Reed
• Cloth Roller
• Picker
• Picking Stick or Arm
• Temple
Warp Beam:
The warp beam, which holds the warp yarns, is located at the back of the machine and is
controlled so that it releases warp yarns to the weaving area of the loom as needed. This beam
is produced by warping.
Healds Shaft:
It is a frame which contain more amount of wire. Every wire contains a hole or eye in its center
through which a warp yarn is threaded. Healds control the warp yarn to produce shed by the
tappet, dobby, or jacquard mechanisms.
Shuttle:
Shuttle is the device used in weaving to carry the weft warn. The picking is completed by shuttle
at shuttle loom. The filling thread is wound on a bobbin which sets into the shuttle or bobbin
container. As the shuttle passes back and forth through the warp shed, it releases thread from
the bobbin and so forms the filling cloth.
Reed:
This is inevitably a combination made up of steel wire rods set vertically in a frame. The spaces
between the wires are known as splits or dents and are kept even and parallel. This is the first
function of reed. Its second function is to feed the filling thread into position. To do this it has to
move in a back-and-forth motion. It attaches the pick with fell of the cloth.
Cloth Roller:
The cloth beam, which holds the fabrics, is located at the front of the machine. The produced
fabric is wind on this beam by take up motion.

Picker:
It is a part which attach with a spindle. It’s got motion from picking arm and this motion help
the shuttle to passing one side to another side. It made by plastics.
Picking Stick or Arm:
It is a wooden arm or stick which give motion on the picker.
Temple:
The parts at the edges of the cloth which supports to maintain fixed dimension in width.
Loom motions:
There are three types of loom motions:
1. Primary
2. Secondary.
3. Tertiary.
Primary Motions
These are the motion which are most necessary in any loom to produce the fabric without these
motions weaving is not possible. These are the fundamental motions of a loom that is why these
are called as primary motions. Primary motions are:
1. Shedding
2. Picking
3. Beating
Shedding:
In this motion the word warp sheet is divided in two layers to form a tunnel known as shed that
is the shuttle can pass through this shed. It can be formed by using tappet dobby or Jacquard
shedding.
Picking:
In this motion a pick of weft passes through the shed from one side to another by the help of a
shuttle. Shuttle is not used for picking in case of shuttle less loom. So picking is the process in
which a weft is pass through the shed.
Beating:
Beating is the process in which the reed beats -up the last pick of weft up to the cloth fell position.

Secondary motion
These motions are next in importance to the primary motions. For continuous weaving these
secondary motions are necessary. So, these motions are call as secondary motions. Secondary
motions are:
1. Take-up motion
2. Let-off motion
Take up motion:
In this motion the cloth roller take up the fabric pick by pick as weaving take place. In this motion
5 wheel and 7 wheels are use.
Let off motion:
In this motion warp yarn are released from the weaver’s beam so that is weaving can take place.
Let-off motion and take up motion works simultaneously.
Tertiary motion
These motions are optional and not necessary but to get high productivity and good quality of
fabric these are very useful motion. Tertiary motions are:
a) Warp stop
b) Weft stop
c) Reed stop
Warp stop motion:
In this motion when there is a warp break due to any reason, the loom stops automatically and
prevent the defect to take place.
Weft Stop motion:
This motion stops the loom, if the weft is not present in the shuttle or there is a missing Weft. It
is a very important motion and helps to improve the quality of fabric.
Reed stop motion:
This motion is used in shuttle loom. This motion stops the loom when the shuttle gets trapped
into the shed and the reed comes forward for beat up This motion protects the reed and warp
yarns from being damage by the shuttle.

Conclusion:
In this experiment we get a clear idea about the basic structure of a Loom/ Weaving machine,
use of loom, how to produce fabric by loom without any damage, different parts of a loom and
their functions, different types of looms and how they work, different motions which are used in
loom. It will have a great impact when we will see it in real life. Though it is online class but our
course teacher tries her best to partiers so that, we can learn a lot.
Reference:
✓ Different Types of Looms | Facts about Weaving Loom Types |
Fibre2fashion.com - Fibre2Fashion
✓ https://www.theweavingloom.com/weaving-techniques-the-best-of/
✓ https://www.fibre2fashion.com/industry-article/3343/different-types-of-
weaves
✓ https://textilelearner.net/primary-secondary-and-stop-motions-of-
loom/#:~:text=The%20conversion%20of%20warp%20sheet,Secondary%20m
otion
✓ https://textilelearner.net/different-parts-of-loom-and-their-functions/
✓ http://textilefashionstudy.com/what-is-loom-classification-of-loom/

Technology (BUFT)
Experiment No: 1.1
Experiment Name: Study on tappet shedding mechanism.
Group: 04 Sec-2B
Lab Report
Taslima Ahmed Tamanna Id. 191-091-801
191-099-801
Date: 17-04-2021 191-100-801

Experiment No: 1.1
Experiment Name: Study on tappet shedding mechanism.
Introduction:
The shedding mechanism separates the warp threads into two sheets (layers) by lifting some of
the heald shafts up whilst lowering others. Tappet is a type of cam to which a rotary motion is
given for the purpose of producing reciprocating motion in rods and levers by sliding contact.
When the rod is to receive a series of lifts, with intervals of rest and thus forms a shed called
tappet. Tappet is generally used for heald shedding. Tappet can be described as an irregular piece
of mechanism to which a rotary motion is given for the purpose of producing by sliding contact,
reciprocating motion in rods and levers.
Objective:
1. To know about the different parts formed this shedding.
2. To learn the mechanism of tappet shedding.
3. To know the construction of tappet shedding.
Apparatus:
1. Tappet Loom
Figure:
Fig: Gearing diagram of tapped loom

Main parts of Tappet Shedding Mechanism:
• Motor.
• Motor pulley.
• M/C pulley.
• Crank shaft.
• Crank shaft gear.
• Bottom shaft gear.
• Bottom shaft.
• Tappet.
• Connecting rod.
• Heald shaft.
Construction of the mechanism:
• Tappet achieve motion from bottom shaft.
• The bowls are placed on the surface off treadle lever.
• Both treadle lever are connected to lever.
• Lamb rods, Heald Shaft, Leather Straps are connected to front side of treadle lever.
Working Principle:
• Tappets are receive motion from bottom shaft.
• When tappets rotate the nose of tappet strike on the bowls of treadle lever which move
down with every strike.
• The treadle lever pull the lamb rod when tappet strike on it. Due to the pulling operation
the heald shaft also move downward.
• There is returning spring set up to the top of the loom frame to send back the heald frame
to previous position.
Description:
Shedding motion is a process of raising and lowering of warp yarns to make a spacing for the weft
yarn to pass through. The raised and lowered form of warp yarns is called a shed. In this motion
a tappet is given a rotary motion so that it depresses a follower and a levers by means of which
the heald shaft operated. Various kinds of shedding tappets are used in industries. They are of
two main types-
1. Negative shedding tappet
2. Positive shedding tappet

Negative Tappet Shedding:
In a tappet shedding mechanism, if the tappet controls only one movement, either an upward or
downward movement of the heald shafts, then the shedding is known as “negative tappet
shedding”. The heald shafts are returned by some external devices like springs, dead weights,
rollers, etc.
Construction of Negative Tappet shedding:
The figure shows a negative Tappet shedding Mechanism. In this a pair of tappets A and B is
fixed to the bottom shaft C at 180° to each other. Two treadle levers D and E are connected to
the R, loom by a bracket F.
Fig: Negative Tappet shedding
The two treadle have teeth to carry the lamb rods G and H respectively. Two heald shafts J and K
are connected to the lamb rods. A top roller reversing shaft Q carry two rollers of different
diameter. The roller of small diameter N is connected to leather strap L to which the front heald
shaft J is connected. The roller P of large diameter is connected to the leather strap M to which

the back heald shaft k is connected. The tappet A and B touch the anti-friction bowls R and S
respectively. The heald shafts have heald eyes T and U through which the warp threads pass X is
the warp sheet and y the cloth.
Working of Negative tappet shedding:
When the bottom shaft rotates in the clockwise direction the tappets are also rotated. The tappet
will press the anti-friction bowl and the treadle. The motion is transferred to the lamb rod. From
lamb rod to heald shaft and leather strap. So, one heald shaft is lowered and it forms the bottom
layer of the shed. The other heald shaft is raised up by the roller reversing motion. It forms the
top layer of shed. So, for one rotation of bottom shaft two sheds are formed. For the next shed
the other set of bowls and treadle works.
Positive Tappet Shedding:
In a tappet shedding mechanism, if the tappet controls both upward and downward movements
of the heald shafts, then the shedding is known as positive tappet shedding.
Construction of Positive Tappet Shedding:
The tappet shaft carries another tappet which has a track in which a bowl is placed. The bowl is
connected to a tappet lever with link rods, links and a heald shaft. Each tappet is separately
connected to a heald shaft through link rods and tappet lever. These are fulcrumed for tappet
lever and links.
Fig: Positive Tappet Shedding

Working of Positive Tappet Shedding:
When the tappet is rotated the bowl is also rotated. As per the shape of track the bowl move up
and down. If the bowl is moved up the tappet lever moves to the right. The heald shaft is lowered.
If the bowl is moved down the tappet lovers move to the left and the heald shaft is raised. As the
heald shaft is moved up and down by the tappet that is why this motion is called as positive
tappet shedding mechanism.
Scope of Tappet Shedding:
1. The Tappet Shedding uses tappets and cams to control the up and down movement of
heald shafts.
2. The tappet shedding is the simplest shedding motion.
3. Tappet shedding can control up to 8 heald shaft.
4. Plain weave, simple twill and simple satin and sateen weave can be produced using tappet
Shedding.
5. Tappet Shedding is the least versatile shedding motion.
Limitation of tappet shedding:
1. Tappet shedding can be used only for simple design.
2. Over shedding strain and a high breakage of warp yarns.
3. It is creating jerky motion.
4. It creates missed shedding.
5. Sometimes unequal shedding happens by lifting one end of the shaft more than the other.
6. Under shedding does not allow (permit) the passage of the shuttle through the shed.
7. Maximum of 8 or 10 tappets can be used in tappet shedding.
Conclusion:
From this experiment we learn tappet shedding mechanism. Tappet shedding machinery is of
import for driving loom. It is likewise of import for stuff design. By this experiment I acquire this
mechanism. This would survive rattling helpful inwards my hereafter life. Though it is online class
but our course teacher tries her best to partiers so that, we can learn a lot.

Reference:
✓ https://textilestudycenter.com/introduction-to-tappet-shedding/
✓ https://textilehelp.org/tappet-shedding-motion/
✓ https://diutestudents.blogspot.com
✓ https://www.textileadvisor.com/2021/03/tappet-shedding-mechanism-negative.html
✓ http://onlinetextileschool.blogspot.com/
✓ https://www.sciencedirect.com/topics/engineering/shedding-mechanism
✓ https://sosopoetry.blogspot.com/

Technology (BUFT)
Experiment No: 2
Experiment Name: Study on dobby shedding mechanism.
Group: 04 Sec-2B
Lab Report
191-099-801
Date: 4-05-2021 191-100-801

Experiment No: 02
Experiment Name: Study on Dobby shedding mechanism.
INTRODUCTION:
Dobby is a shedding mechanism placed on the tiptop of the loom inwards club to hit figured
patterns yesteryear using large let on of healds than the capacity of a tappet. Dobby is every bit
good known every bit a “witch or “wizard. Dobby is a shedding device attached to loom to
increased the designing capacity. The dobby normally controls 12 to 24 hold shafts the dobies
are classified as negative or positive, single lift, double lift, crank driven, cam driven etc. The
dobby forms bottom closed, center closed, semi open and open type of shed. The dobby is also
classified as left hand and right hand. The right-hand dobby is one which is placed at the left-
hand side of the left hand. It gets drive from left hand end loom. The left-hand dobby is one
placed at right hand side of left-hand loom. Left hand dobby gets its drive from right end of the
loom. This is a compact, electronically guided shedding motion and capable of getting up to
twenty-eight shafts. additional complicated and versatile shedding motion. A dobby loom,
therefore, will have up to twenty-eight shafts, and far larger weave repeat is possible. the design
could also be woven with 2 or additional basic weaves and their variation. Such fabrics could also
be referred as dobby cloths or dobby weave, towels typically show geometric designs when the
pattern is provided by dobby.
Objectives:
To know about the different parts formed this shedding.
To learn the mechanism of dobby shedding.
To know how to work the dobby shedding mechanism.
To acquire the machinery of dobby shedding.
Apparatus:
Dobby loom
Description:
Classification of dobby:
1. According to lift:
(a) Single lift
(b) Double lift
2. According to figuring capacity (no. of Heald shaft):

48’s, 36’s, 24’s, 20’s, 16’s, 12’s
3. According to the position of the Heald shaft:
(a) Vertical
(b) Horizontal
4. According to the driving of Heald shaft:
(a) Positive
(b) Negative
5. According to shed:
(a) Bottom close shed
(b) Centre close shed
(c) Semi-open shed
(d) Open Shed
6. According to no. of jack lever:
(a) Single jack lever
(b) Double jack lever
7. Broadly dobby shedding:
(a) Ordinary dobby (i.e., single jack lever, single lift dobby)
(b) Special dobby (i.e., double jack lever, 48’s dobby)
Dobby shedding mechanism:
The dobby consists of three principal mechanisms:
The drive mechanism: An auxiliary shaft is permanently driven from the weaving machine.
-It operates two steel bars (knives), having a regular reciprocating motion nor
-It operates coupling rings on a rotary dobby.
The selection mechanism: It is operated by a dobby card or by some form of pattern chain.
-It reads or checks the design information punched on a dobby card, and transmits the
necessary movement from the drive mechanism to the lifting mechanism.
The lifting mechanism: operates the Heald shaft motion.

Fig: Three principal mechanisms
The scope of Dobby:
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.
Main parts:
Bottom shaft.
Driving shaft.
T-lever.
Fulcrum.
Upper draw knife.
Lower draw knife.

Upper hook.
Lower hook.
S-lever.
Timber lever.
C-link.
Pivot.
Out & inside jack lever.
Connecting cord.
Heald shaft.
Return spring.
Motor.
Motor pulley.
Machine pulley.
Crank shaft.
Negative Dobby Shedding:
In this variety of shed, lowering of the Heald frame occurred automatically.
Construction:
Two knives K1 and K2 are connected with T-lever, which is driven by the dobby driving shaft
which in turns gets motion from the bottom shaft. The upper hook and lower hook get movement
by the upper knife and lower knife.at the two ends of S-lever, the two hooks are joined. Outside
jack lever joined with the baulk lever by timber lever and inside the jack, lever joined with baulk
lever by link with the outside and inside jack lever the two ends of the Heald shaft joint. Two
feelers P & Q are used to activate two hooks. P feeler is directly connected with the lower hook
& Q feller is joined with the upper hook by a needle.

Fig: Negative hook and knife dobby (Climax)/Double jack lever Double lift Dobby Mechanism
The two feelers are fulcrum at a point. There is a patterned cylinder below the feelers. according
to fabric design, there is a peg chain in the pattern cylinder.
Working principle:
T-lever gives outward and inward movement When the connecting rod moves up and down.
According to fabric design, when peg came in contact with the feeler, then the right portion of
the feeler is raised and the left portion is lowered. As hooks are supported with the feeler, hooks
are lowered. When the left end of feeler Q is lowered, then upper hook cam in contact with the
upper knife. As a result, the upper portion of S-lever moves to the right. As the bulk lever is joined
with S-lever bulk lever also moves to the right side.
Similarly, when the left end of feeler P is lowered, then the lower hook came in contact with the
lower knife. As a result, the bottom portion of S-lever moves to the right & the same process
occurs i.e., the top portion of the baulk lever moves to the right, and then jack levers are moved
up at the same time. Hence the heald shafts are again raised. By the upper knife & lower knife
thus a heald shaft is alternately raised. The shaft will, therefore, be lowered with the help of
return spring and will remain down for next pick.

Ruti Cam Dobby:
The ruti cam dobby is negative in action i.e., the heald are lowered because of the spring in this dobby.
Fig: Ruti Cam
The knives are pushed forward by the pair of cams. The knive will come back and always in the
contact with the cams because of the spring. Here dwell of about 1/3 pic is achieved. The
selection of the hook is made by paper pattern instead of wooden pegs.
Positive Dobby Shedding: Principles of positive dobby, in this variety of shed lifting &
lowering of the heald frame, each is possible. lifting is occurred by means that of jack & lever,
and lowering is occurred by means that of spring under tension.

Fig: positive dobby mechanism
Construction and Working Principle:
Positive dobby shedding is that the combination of 3 Cylinders, jack lever, spring and a shaft.
Between the 3 cylinders, a shaft is a pin in one side the upper cylinder moves because the
opposing clockwise and lower cylinder moves because of the clockwise direction. the main
cylinder when getting motion from the shaft when it found peg or pattern plan then the cylinder
connected to the higher half-toothed disc. so the heald frame is up,& when the pattern cylinder
doesn’t found peg then the main cylinder connected to the lower half-toothed disc and also the
spring retains the heald frame to the downward direction.
Positive Cam Dobby:
The positive cam dobby is called positive because lifting and lowering of the heald is made
positively. The dobby has cam which will give oscillation to the griffel and returning bar through
the lever i.e. when the griffel is engaged with the hook it will pull one side bulk and at the same
time return bar push the other side of the bulk.

Fig: positive cam
Suppose heald is to be kept down on the next pick, the bottom hook will not engaged in the
griffel, it is looked in the locking bar and thus engaged in the griffel, it is looked in the locking bar
and thus other end of the bulk will not move even the upper return bar pushes to the bulk
towards the stop and heald will be down. in short it return bar stop and locking bar together
make the dobby positive along with grooved cam.
Application of Dobby
• Shirts
• Dresses
• Outerwear
• Polo shirts
• Handbags
Dobby weaves also produce allover figured fabrics. They are made on looms having a dobby
attachment, with narrow strips of wood instead of Jacquard cards. Dobby weaves are limited to

simple, small geometric figures, with the design repeated frequently, and are fairly inexpensive
to produce. A good example of dobby weave is stripes or waffle cloth but the designs need to be
straight vertically or horizontally. Heavyweight dobby fabrics are used as home furnishings and
for heavy apparel.
Advantages And Disadvantages Of Dobby Shedding
Advantages:
● Highly complex and critical fabrics can be weaved.
● At a time it can control many heald frame
● More faster than the positive dobby as well as over conventional loom
● Can produce close bottom shed.
● In this loom many numbers of healds can be used for weave a figured fabrics.
● Particularly 12-24 healds can be used in a cotton industry to weave fabrics.
● In which fabrics are not possible to weave in tappet shedding loom and jacquard
loom for increasing the production cost, to weave this kind of fabrics dobby are used
extensively.
Disadvantages:
● In this shed only lowering of the shed is possible
● Due to more stress, yarn breakages more
● It is not good for heavier fabric
● It does not provide more high speed to the loom
● The adjustment of dwell is complicated.
● Maintenance cost is so high.
● Comparatively cost is high than tappet loom.
● Less productivity than tappet loom.
● Less speed.
Conclusion:
Dobby loom is of import for its use. We tin move 8-12 heald frame inwards tappet loom but if
nosotros desire to move to a greater extent than heald frame for to a greater extent than
decorative blueprint thus nosotros should move dobby loom. This practical helps me to know
nearly the dobby loom in addition to its mechanism. I intend this volition assistance me inwards
my hereafter life.

Reference:
https://www.textilesphere.com/
https://textile-in.blogspot.com/
https://textilelearner.net/
http://textilecreativities.blogspot.com/
https://textilemerchant.blogspot.com/
http://vasantkothari.com/
https://www.scribd.com/
https://textile-edu-services.blogspot.com/

BGMEA University of Fashion & Technology
Course Title: Fabric Manufacturing Engineering-II (Lab)
Lab Report
Experiment No: 03
Experiment Name: Study on picking mechanism of a shuttle loom
Lecturer, BUFT
Department of TE
191-091-801
191-097-801
191-098-801
191-099-801
191-100-801
Group: 04
Sec-2B

Introduction:
Picking: Picking motion is a primary motion which comes after shedding motion. When the shed
gets almost opened, the pick (weft yarn is inserted into the shed from one selvedge to another
selvedge. The fabric weaving is not possible without picking motion. There many kinds of picking
motions are used to weave a fabric.
Conventional Picking: It is the oldest technique of weft insertion on the loom. The picking
media may be a wooden shuttle that traverses back and forth across the loom width. A pirn or
quill having yarn wound thereon is placed inside the shuttle. because the shuttle moves across,
the yarn is unwound and placed within the shed. A picking stick on all sides of the loom helps to
accelerate the shuttle by striking it. The shuttle travels on the race board, above the lower portion
of the warp sheet. The shuttle picking takes place from both the edges of the loom.
Method: 1) Mechanisms will generate the energy for picking when it is required.
2)Done by means of cam to displace the picker.
Example shuttle loom
Modern picking: In the modern machine weft yarn insertion system different type. In these
machine motion very first and we will get more production.
Method: Mechanisms will generate the energy required for picking and stored in springs or
torsions and release it suddenly when it required.
Example: Projectile loom

Classification of picking:
Fig: classification of picking

# For Over picking mechanism:
Over picking:
This motion is used for cotton and jute looms. In this motion the picking shaft is mounted over
the shuttle box. Picking is done over the loom that is why it is called as over pick motion.
Objectives:
1. To know the over picking mechanism.
2. To identify the different parts of this mechanism.
3. To learn the construction of over picking mechanism.
Apparatus:
1. Loom/ Weaving machine.
2. Weft yarn.
3. Cloth beam.
4. Weaver’s beam.
5. Shuttle.
Description: Picking Mechanism involves the insertion of the weft yarn through shed across
the width of the warp sheet. The picking mechanism is especially a function of the picking
media, used for the insertion of the weft. The picking media vary greatly on the idea weft
velocity and therefore the insertion rate; and are classified into the shuttle and shuttle-less
picking. If the picking is done due to picking arrangement situated upon the shuttle box then
it is called over picking.

Diagram Of Over Picking:

Main Parts:
1. Picking Strap
2. Picking spindle
3. Shuttle
4. Picker
5. Picking stick
6. Angular adjustment
7. Bearing
8. Cone
9. Bottom shaft
10. Timing adjustment
11. Footstep bearing

Construction:
It contains a vertical picking shaft, placed either inside or outside of the framing. The picking shaft
consists of a shuttle spindle which is passed through a slot in picking shaft. Picking tappet placed
in contact with picking cone.The picking tappet mounted on bottom shaft.
A spiral spring is connected to the picking shaft returns the cones to the surface of the picking
tappet after every throw. The picking tappet is made up of three parts Boss, shelf, nose. Three
leather straps namely check strap, spindle strap, & control strap used to ease the impact of the
incoming shuttle.
Working principle:
1. Bottom shaft drives the picking tappet.
2. In revolving picking tappet nosse, stick the cone shaped antifiction roller on the stud &
partly rotates the picking shaft & lever.
3. picker gets angular movement from the to & for movement of picking arm which is
responsible drive with sufficient velocity to drive the shuttle across the loom.
4. When picker strikes the shuttle the shuttle moves into the open shed through race board.
5. Picking is done.
6. The spring causes the picking arm & picker to move back after the delivery of pick.
Mechanism of Over Picking:
Over picking mechanism is used on cotton and jute loom. It is robust and easy to adjust and
maintain. The spindle is situated over the shuttle box and is essential to guide the shuttle along the
correct path. It is normally set slightly up and slightly towards the front of the loom and its inner
end.
The back end of the shuttle will thus receive a similar lift at the end of the stroke, so that its leading
end will receive correct delivery down and into the shed. A flexible leather-picking strap is used
to control the picker, which has tendency to stretched slowly in use, and vary with regard to its
elastic property.

The cone over pick motion consist a vertical shaft placed either inside or outside the loom framing.
The shaft serves as fulcrum of the picking arm, it is held against the loom frame. There is a spiral
spring at the picking shaft, which causes the picking arm and picker to move back after the delivery
of the pick.
At the two end of the bottom shaft, two picking cams are fixed. In revolving its nose the tappet
strikes the cone shaped ant frictional roller strut, positively rotates the shaft and causes the pick to
move inward with sufficient velocity to drive the shuttle across the loom. The timing of the picker
begins to move can be attend by turning the picking tappet on its boss.
Uses:
This is used for narrow and fast running looms, weaving light and medium weight fabrics and for
many narrow and wide looms for weaving heavy fabrics.

# Under picking Mechanism:
Under Picking: Since complete picking mechanism is mounted under the loom in this motion
and picking stick also hits the shuttle under side of the loom, so that this mechanism is called
under pick motion.
Objective:
1. To know the under picking mechanism.
2. To identify the different parts of this mechanism.
3. To learn the construction of under picking.
4. To learn about side lever under picking mechanism.
5. To learn about side lever under picking mechanism.
6. To learn about different parts used in this mechanism.
Apparatus:
1. Loom/ Weaving machine.
2. Weft yarn.
3. Cloth beam.
4. Weaver’s beam.
5. Shuttle.

Machine parts:
• Bottom shaft
• Circular Disk
• Picking Bowl
• Picking Shoe
• Side Lever
• Pivot
• Guide
• Elbow
• Picking Stick
• Returning Spring
• Rocking Shaft
• Buffer
• Picker
• Shuttle Box
Features of under picking mechanism:
1. Picker arm is placed under the race board.
2. Suitable for wider loom.
3. Under picking works less smoothly.
4. More direct action.
5. Rough in action.
6. More clean mechanism.
7. Consumes more power.
8. Used for heavy weight fabrics in silk and rayon looms.

Under picking mechanism:
In under picking mechanism a race board is situated over the picking arm. Under picking is
controlled by picking cam which is fixed on the bottom shaft. At first the motion comes from
motor and machine pulley.
Then the motion comes in to the bottom shaft and thus picking cam. When picking cam rotates
and its nose portion comes in contact with treadle lever and pushes it then the treadle lever pushes
the angular lever. The picking arm gets motion from angular lever which is connected with picking
arm.
A picker is placed in the picking arm which pushes the shuttle. When shuttle gets motion by
picking arm then shuttle begins to move to and from on the race board. Thus picking is done.
A spring is situated which causes the picking arm and picker to move back after the delivery of
the pick. At the two end of bottom shaft, two picking tappets are fixed. By increasing nose length
picking speed may be increased.
Construction:
1) the circular disk received motion from the bottom shaft. The disk contain a bowl named picking
bowl able to push down the picking shoe of side lever.
2) Side lever of loom pivoted with loom frame and the up-down motion of side lever is controlled
by fixed guide.
3) Side lever is connected with elbow of picking stick which attached with returning spring on the
top of rocking shaft.
4) Each picking stick contains picker which push the shuttle through the passage.

Working Principle:
Due to motion of circular disk the picking bowl strike on picking shoe. For the strike lever pushed
down. The front side of the lever push the elbow of picking stick, the result picking stick move
forward and it hit the picker which push the shuttle to insert weft and the pushing force is enough
to send the shuttle to opposite shuttle box.
Over Pick Under Pick
1. Arm position is above the shuttle box. 1. Arm position is below the shuttle box.
2. Higher loom speed. 2. Lower loom speed.
3. Less power required. 3. More power required.
4. Works more smoothly. 4. Works less smoothly.
5. Less clean mechanism. 5. More clean mechanism.
6. Less direct action. 6. More direct action.
7. Comparatively gentle in picking
action.
7. Comparatively harsh in picking
action.
8. Less wear and tear. 8. More wear and tear.
Uses:
This mechanism is used in all non-automatic cotton looms. It is also used in jute looms.

#Modern Loom for picking mechanism:
The warp yarn are let off by warp let-off mechanism. Shed formation is there to separate the
sheets of warp yarns into two sheets upper and bottom. Then a weft yarn is passed into the
middle of the two sheets of warp yarn by means of any weft inserting media whether shuttle
projectile or jet mechanism (air, water). After the picking completed beat up of weft yarn to the
feel of cloth done by means of reed. After wards fabric wounds on the cloth roller which is take
up mechanism.
Advancement in weft insertion system:
1.Projectile weaving machine.
2.Rapier weaving machine.
3.Air-jet weaving machine.
4.Water-jet weaving machine.
These discuss is below: -
Projectile: Two types of projectile looms are used. In one, the projectile travels only in
one directions returned to the starting point by a conveyor belt. To maintain the weaving
speed, each machine must have several projectiles, although only one is in use at any
one time. It is called multiple-prtile systems. They can be used in machines with a wide
weaving bed so the projectile grippers can transfer the pick across the fabric in a relay
fashion. In other multiple-projectiles systems, the gripper from the first projectile picks up
yarn from the supply source and moves across the shed to lay that length of yarn; then,
as beat-up occurs, the projectile drops into a conveyor system that returns it to the supply
side to pick up
new yarn. In the meantime, the second gripper has pulled a pick to repeat the process.
In the other type of gripper machine, a single gripper inserts one weft yarn alternately
from the right- and left- hand sides of the loom. It is called single picking system. This
system picks up yarn on the supply side and carries it the entire width of the shed. After
beat-up has occurred, the projectile picks up yarn from a second supply source on the
other side and returns across the shed to place the next pick. The gripper serves the

same function as a conventional shuttle, but instead of holding a pirn, it carries the yarn
behind it. Packages of yarn must, therefore, be placed on both sides of the machine.
Each pick is individually cut, so there is not a continuously woven selvage like that
produced by a shuttle machine. Instead, the edges are fringed. To finish them, a tucking
device is used on both sides to interlace the fringe with the last few warp yarns along
each edge.
Rapier: Rapier loom is a shuttle less weaving loom in which the filling yarn is carried through
the shed of warp yarns to the other side of the loom by finger like carriers called rapiers. There
are two type of Rapier. 1.Single Rapier and 2. Double Rapier
The rapier head on creel side picks up yarn from designated cone and is carried towards center
of warp shed by the rod. Simultaneously the matching rapier head from opposite side moves in,
as shown in the central diagram. The picking cycle is completed when both rapiers retreat to
their original position.
Air jet: Air-Jet System Uses a high pressure air to insert the filling yarn into warp shed. Air jet
weaving loom is that, at which jet of air is used to propel the weft yarn through the shed at a
speed of up to 600 ppm.
The air jet weaving machine are supplied with compressed air maintained from central source •
The preparation of the air before its distribution of the air to the individual weaving machine
through a valve system • Filtering • Compressing • Cooling • Drying • Air tank.
Water Jet: A water Jet is the machine for weaving cloth (loom) which use a Jet of Water to insert
the weft (crosswise threads) into the warp (length wise threads) The force of air water carriers
the yarn from one side to the other.
The weft yarn, which is fed from cone is drawn-off by a feeding and measuring device and then
passes through a tension regulator and a weft clamp. When the insertion has to take place, the
weft clamp loosens its hold and the thread inserted inside a nozzle is struck by a jet of pressurized
water and launched through the shed at high speed. After the insertion has taken place, while
the weft is held flat by the threads which are moved by the leno mechanisms the thermal knives

enter into action on the launch side to cut the weft, and on the opposite side to trim the fabric.
A yarn clamping device holds the weft waste which is cut off by the right-handed thermal knife
while rotating gears arrange for its removal (center selvedge).
Conclusion: This picking mechanism is very important for loom. In the loom under picking
is directly done by picker and picking arm. Again, under picking is necessary for weft yarn
insertion. So, we should learn about this mechanism very carefully, this experience will help us
in our future practical life.
Reference:
1. https://www.textileadvisor.com/2019/09/picking-motion-primary-loom-motion.html
2. https://textilestudycenter.com/modern-techniques-weft-insertion-projectile-weaving-
machine/
3. https://textilesfashion.com/picking-mechanism/
4. http://textilestore.blogspot.com/2014/02/experiment-name-study-on-picking.html
5. https://www.slideshare.net/muralikrishnan71697092/picking-mechnaism-in-weaving
6. https://slideplayer.com/slide/13887431/
7. http://onlinetextileschool.blogspot.com/2013/09/experiment-name-study-on-over-
pick.html
8. http://www.definetextile.com/2014/04/picking.html

Technology (BUFT)
Experiment No: 4
Experiment Name: Study on beat-up mechanism.
Group: 04 Sec-2B
Lab Report
191-099-801
Date: 10-06-2021 191-100-801

Experiment Name: Study on beat-up mechanism.
Introduction:
The beating or beat-up is the third primary motion of weaving. It is also the last operation of the
loom in weaving in which the last pick inserted in the fabric is ‘beat’ into position against the
preceding picks. It consists in driving the last pick of weft to the fell of the cloth. This is
accomplished with the help of a reed fixed in the sley. The sley is given a sudden and quick
movement towards the fell of the cloth by the cranks in the crankshaft. The sley wood runs from
one shuttle box to another, and when at its backward movement, the shuttle travels over its race.
There are different types of beat-up mechanism in weaving, depending on several factors. But
mainly, two types of beating are considered in general based on the operating element. One is
crank and crank-arm beat-up (used in shuttle loom), and another is cam best up (mostly used in
the shuttle less (loom). However, the related parts of the beating process remain constant
irrespective of whether the main motion comes from crank or cam. The basic difference in
between this is the source of motion of the sley, whereas this sley motion ultimately controls the
overall parameters of beat-up.
Objective:
I) To learn about the beating-up mechanism of crank shaft.
II) To learn about different types of parts related with the mechanism.
III) To calculate the speed of the mechanism.

Apparatus:
Loom
Classification:
❖ According to no. of beat up-
Single beat up
Double beat up
❖ According to beat-up mechanism-
Conventional beat up/Crank and crank arm beat up
Cam beat up/Modern beat up
❖ According to movement of reed-
Real beat-up
False beat-up
❖ According to position of fell of the cloth-
Fixed fell beat up
Moving fell beat up
Types of beat-up mechanisms:
There are several types of mechanisms used for achieving the required motion of sley. They are
mainly divided into two:
➢ link-type beat-up mechanism
I) Four-link
II) Six-link
III) Multi-link
➢ cam operated beat-up mechanism
I) special mechanisms
Single beat-up mechanism/Crank beat up mechanism:
I) The beating up mechanism is connected with crank shaft. Here crank shaft is connected
with machine pulley.
II) The crank shaft contain crank. Each crank connected with crank arm by crank pin and it
contain bearing for smooth operation.
III) Crank arm and sley sword are attached with sword pin.
IV) Position of the reed is top of the sley race.
V) Reed cap placed on the top of the reed.
VI) The whole parts of the beating up mechanism are mounted on rocking shaft.

Figure:
Main parts:
1. Crankshaft
2. Reed
3. Crank
4. Sley race
5. Crank arm
6. Sley
7. Reed cap
8. Sley sword

Description:
The crankshaft gets drive from motor via motor pulley and machine pulley. The crankshaft has
two cranks. These cranks transform the rotary motion into swinging motion. The reed cap is
connected by crank arm to crank of the crankshaft. Again, the reed is connected between reed
cap and sley. There is sley sword under the sley that is bolted to the rocking shaft. There is also
shuttle box on the sley. Now the crank gives the swinging motion to the sley by crank arm. When
the sley is moving towards the Heald shaft at certain position the shuttle passes through warp
shed. Again, when the sley is coming towards the front rest at last position the reed pushes the
last pick to the previous pick of cloth. This is the beating-up motion and the cloth increases in
lengthwise in this way.

Working Principle:
✓ For beating up process, the sley sword must reciprocates, the sley sword is connected to
the rocking shaft for this purpose.
Fig: Single beat-up mechanism/Crank
✓ When the crank of the crank shaft rotates and comes in forward position (at 90°), then
it pushes the crank arm forward. Thus, crank arm gives to and from movement.
✓ As the crank arm is connected to the sley race and reed is situated above the reed race,
reed also moves forward as the crank arm move forwards. The reed pushes the weft in
the fall of the cloth. In this mechanism, one beat up is done for every picking.
Double Beat Up Mechanism:
Construction by a sley sword, a crank, a connecting arm, two arms one of them is hinged to the
framing & other is attached to sley by usual connecting pin. The sley is wooden frame
accommodating two shuttle boxes, a sley race, a reed, a reed cap and two sley-swords. It swings
forward and backward. At its forward motion, the last pick of weft is beaten up to the fell of the

cloth, and at its backward motion the shuttle is allowed to pass over the sley-race through the
shed. So, its forward
Fig: Double Beat-up mechanism
center position is known as beating up position and the back center position is called shedding
and picking position.
Working principle:
✓ In one drawing the arms E & F are straight but when the crank moves to the top center it
is pushed up & E, F are bent.
✓ When the crank moves & there comes a stage when the arm become straight & a beat-
up is done by the system.
✓ When the crank again moves up, the knuckle joint moves up & again the arms become
straight & cause beat-up.
✓ Hence the two beat-up is done for a pick.
✓ The time, that elapses between the first & second straightening, can be increased either
by moving the crank center up or by lengthening the crank arm.
✓ Lowering the crank or shortening connecting arm can reduce time.

✓ Lengthening the size of the crank the force of beat up may also be increased.
The sley gets motion from the rotation of crank via a crank arm. When the crank shaft rotates it
pushes and pulls the sley with the help of it pushes and pulls the sley with the help of the crank
arm in forward and backward direction.
Purpose of beating up:
To push the newly inserted weft to the feel of the cloth.
To produce compact fabric.
Factors influencing the Beating Force:
Pick Spacing
Weft Yarn Linear Density
Timing of Shedding
Warp Tension
Conclusion:
To make a woven fabric interlacement of warp and weft yarns is the main condition. That’s why
beat-up mechanism is a very essential motion for weaving. Proper setting and adjustment should
be taken for this motion. This practical helps me to know about beating-up motion. It would be
much better if we could see the machine in in real life. It will have a great impact when we will
see it in real life. This will help us in the upcoming experiment of this course and it will also helpful
for future professional life.
Reference:
https://textile-in.blogspot.com/
https://textilelearner.net/
http://textilecreativities.blogspot.com/
https://textilemerchant.blogspot.com/
http://vasantkothari.com/

Technology (BUFT)
Experiment No: 5
Experiment Name: Study on Take-up mechanism.
Group: 04 Sec-2B
Lab Report
191-099-801
Date: 14-06-2021 191-100-801

Experiment No.: 05
Experiment Name: Study on Take-up mechanism of a weaving machine/Loom.
Introduction: Take-up is to draw a fabric to the cloth roller regularly as it is woven. Texture of
a fabric largely depends upon the number of ends and picks per centimeter or inch. This motion
determines the number of picks of weft per inch or centimeter and contributes to the uniform
texture of the fabric. It is the work of the weaver for accurately fixing the position of the fell of
the cloth before starting a loom. The process of withdrawing fabric from weaving zone at a
constant rate and then winding the woven cloth on the cloth roller with the continuous progress
of weaving is called take up motion. This motion withdraws fabric from the weaving area at the
constant rate that will give the required pick spacing and then winds it onto a roller.
Objectives:
To wind the woven fabric on the cloth roller with progress of weaving.
To maintain uniform picks per inch.
To know about the construction of the mechanism.
To know about drive of the take-up motion.
Description:
Take - up motion:
Take-up is to draw a fabric to the cloth roller regularly as it is woven. Texture of a fabric largely
depends upon the number of ends and picks per centimeter or inch. The main objectives of the
take - up motion are to pull the fabric forward after beating of every inserted pick and to maintain
the picks per inch required in the fabric. When the beating is completed, loom reed starts to
change the position, it reaches to back dead center position and gets remained stationary during
picking. The reed again performs beating motion. This cycle gets repeated periodically. The
position of the fell of the cloth starts to shift its position toward the reed in the absence of a
suitable continuous fabric pulling mechanism. Thus, a suitable and continuous fabric pulling
mechanism keeps the fell of the cloth position unchanged during continuous weaving. In this
way, we can say that " A continuous fabric pulling mechanism which helps to keep the fell of the
cloth position unchanged during continuous weaving process is called take - up motion". This
motion determines the number of picks of weft per inch or centimeter and contributes to the
uniform texture of the fabric. It is the work of the weaver for accurately fixing the position of the
fell of the cloth before starting a loom.

Fig: Take-up motion
Types of motions
According to drive:
➢ Positive take up
➢ Negative take up
According to motion of the cloth/Rate of take up:
➢ Continuous
➢ Intermittent
According to drive given to the cloth roller:
➢ Direct drive
➢ Indirect drive
According to number of gear train:
➢ 5-Wheel
➢ 6-Wheel
➢ 7-Wheel
➢ Worm wheel
According to brand name:
➢ Sulzer
➢ Pickanol
➢ Toyota

Main parts:
➢ Sley
➢ Sleys word
➢ Connecting rod
➢ Monkey tail
➢ Holding/Catching/Locking pawl.
➢ Pulling pawl
➢ Rachet Wheel
➢ Standard wheel
➢ Change wheel
➢ Sewing wheel/Pinion
➢ Stud/Compound wheel
➢ Stud/Compound Pinion
➢ Take up wheel
➢ Take up roller
➢ Cloth roller
Motion Transfer:
Sley sword to connecting rod→ Connecting rod to monkey tail→ Monkey tail to pawl→
Pawl to ratchet wheel→ Ratchet wheel to standard wheel→ Standard wheel to change wheel →
Change wheel sewing wheel→ sewing wheel to stud wheel→ Stud wheel to stud pinion→
Stud pinion to take up wheel → Take up wheel to take up.
Working Principle:
The motion is primarily imparted from the sley sword→ The sley sword is connected to the slay
that gets motion from crank shaft and the crank shaft gets motion from motor by gearing→ At
the bottom of sley sword a connecting rod is connected which passes the motion to the monkey
tail. The monkey tail is fulcrum with two pawls: the upper is holding pawl and lower is pulling
pawl→ These two pawls are mounted freely to the ratchet wheel which is connected with the
standard wheel by shaft→ Over the standard wheel the change pinion is geared→ The change
pinion is connected with the stud pinion by shaft and the stud wheel is geared with the stud
pinion upon it→ The swing pinion is connected with the stud wheel and the cloth take-up roller
wheel is geared with the swing pinion.
The cylinder upon which the woven fabric is wound, is connected with this wheel by shaft→ Now
when the sley moves one time after one pick insertion the connecting rod pass this motion to the
monkey tail and as the pawls are fulcrum with monkey tail they get downward motion→ Using
this downward motion the pushing pawl pulls the rachet wheel one time and the holding pawl

holds the rachet in this position→ Finally the cloth roller gets the motion by gear train and thus
fabric is wound on cloth roller continuously with the weaving of fabric.
7-wheel take up mechanism:
In this take up mechanism a train of seven wheels is used. Seven wheel take up motion is an
intermittent take up motion. This mechanism receives motion from slay sword. When the crank
shaft rotates, the slay sword receives to and from motion from crank shaft.
Fig: 7-wheel take up mechanism

Related Machine Parts:
➢ Ratchet wheel
➢ standard wheel
➢ Change wheel
➢ Change pinion
➢ Compound wheel
➢ Compound pinion
➢ Take up roller wheel
➢ Take up roller
➢ Pushing pawl
➢ Pulling pawl
➢ Finger fulcrum
➢ Finger
In this mechanism take up lever connect both sley sword ad ratchet wheel. For beat up
the ratchet wheel move due to push by the pawl.
Ratchet wheel connected with standard wheel.
Standard wheel connected with change wheel and change wheel attach with change
pinion by shaft.
Change pinion transmit motion to compound wheel which is connected with compound
pinion by shaft.
Compound pinion transfer motion to take up wheel which connected with take up roller.
Working Principle:
The motion is primarily imparted from the sley sword. The sley sword is connected to the sley
that gets motion from crank shaft and the crank shaft gets motion from motor by gearing. At the
bottom of sley sword a connecting rod is connected which passes the motion to the monkey tail.
The monkey tail is fulcrum with two pawls: the upper is holding pawl and lower is pulling pawl.
These two pawls are mounted freely to the ratchet wheel which is connected with the standard
wheel by shaft. Over the standard wheel the change pinion is geared. The change pinion is
connected with the stud pinion by shaft and the stud wheel is geared with the stud pinion upon
it. The swing pinion is connected with the stud wheel and the cloth take-up roller wheel is geared
with the swing pinion. The cylinder, upon which the woven fabric is wound, is connected with
this wheel by shaft. Now when the sley moves one time after one pick insertion the connecting
rod pass this motion to the monkey tail and as the pawls are fulcrum with monkey tail, they get
downward motion. Using this downward motion, the pushing pawl pulls the ratchet wheel one

time and the holding pawl holds the ratchet in this position. Finally, the cloth roller gets the
motion by gear train and thus fabric is wound on cloth roller continuously with the weaving of
fabric.
5-wheel take up motion:
Five wheels take up motion is an intermittent take up motion. A train of five gears is used in these
five wheels take up motion mechanism. This mechanism receives the motion through slay sword
by a connecting rod. One end of connecting rod gets connected to the slay sword with the help
of stud. This end of connecting rod gets free to rotate in both directions.
Fig: 5-wheel take up motion
Related Machine Parts:
I - fulcrum
G - pushing pawl
E - ratchet wheel
F - change pinion
A - beam wheel
B - pin roller or take up roller or emery roller
H - catcher
C - stud wheel
D - stud pinion
J – finger

It consists of a train of five wheels. Of these five wheels ratchet, stud and cloth roller wheels are
driven wheels while change and stud pinions are driver wheels. The motion is primarily imparted
from the sley sword. The sley sword is connected to the sley that gets motion from crank shaft
and the crank shaft gets motion from motor by gearing. At the bottom of sley sword a connecting
rod is connected which passes the motion to the monkey tail. The monkey tail is fulcrum with
two pawls: the upper is holding pawl and lower is pushing pawl. These two pawls are mounted
freely to the ratchet wheel which is the 1st wheel of this mechanism. The ratchet wheel is
connected with the change pinion by shaft which is the 2nd wheel. Under the change pinion the
3rd wheel named stud wheel is geared. This wheel is geared with the stud pinion, the 4th wheel.
The 5th wheel is take-up roller wheel which is geared upon the stud pinion. The cylinder, upon
which the woven fabric is wound, is connected with this wheel by shaft. Now when the sley
moves one time after one pick insertion the connecting rod pass this motion to the monkey tail
and as the pawls are fulcrum with monkey tail, they get upward motion. Using this upward
motion, the pushing pawl pushes the ratchet wheel one time and the holding pawl holds the
ratchet in this position. Finally, the cloth roller gets the motion by gear train and thus fabric is
wound on cloth roller continuously with the weaving of fabric.
Working Principle:
When the sley moves backward the stud in the slot of take-up lever also moves backward and
the pushing pawl moves forward and push one or two teeth of ratchet wheel. Due to this the
ratchet wheel moves and the motion transfers to change wheels from change wheel the stud
wheel also rotates and from the stud wheel the motion get transfers to stud pinion. The stud
Pinion is in contact with the emery roller end wheel. So, it will rotate the emery roller end wheel
and the motion is transferred to take up roller. The take up roller rotates and the cloth gets wind
up on to the cloth roller pick by pick.
Advantages of 7-wheel over 5-wheel take up mechanism:
➢ It can give a larger number of picks per inch in cloth from a small stock of wheels by changing
two wheels in the train,
➢ It can give even a fraction of a pick per inch in cloth and
➢ The number of teeth in the change wheel and the number of picks per quarter-inch has been
simplified.

Worm wheel:
The worm wheel, also known as the worm gear, is simplistically a helical gear that matches the
pitch, pressure angle, and helix angle of the worm. The significant difference between a worm
gear and a helical gear is the throat. This is an indent in the tooth form that allows the worm to
be properly seated with the centerline of the worm wheel. The speed ratio of a worm gear pair
is determined by the number of teeth on the worm wheel and the number of thread starts on
the worm. For worms with a single thread, very high-speed ratios can be developed. Since the
speed ratio is the ratio of the number of teeth to the number of thread starts, it is possible to
change the reduction ratio by replacing the worm pair with another set which is produced with
additional starts. With the addition of more thread starts, the helix angle needs to increase if the
center distance is to remain the same.
Fig: Worm wheel
In this type of motion, a worm and worm wheel drive are used to drive the take up roller. This
motion is continuous and cloth is drawn forward and wound on to the cloth roller by frictional
contact with the take- up roller.

Conclusions: By this experiment we know about how to cloth is collected by take up
mechanism, motion transfer and advantages 7-wheel over 5-wheel take up mechanism. We also
learn the different wheel of this mechanism. This practical helps me to know nearly the take-up
mechanism and addition to its different types of wheel motion. I intend this volition assistance
me inwards my hereafter life. Though it is online class but our course teacher tries her best to
partiers so that, we can learn a lot.
Reference:
http://textilelearningplatform.blogspot.com/
https://textilestudycenter.com/motion-of-loom/
https://bdtextileengineering.blogspot.com/
https://www.textileadvisor.com/
https://textilefashionstudy.com/
https://en.wikipedia.org/wiki/
https://www.sciencedirect.com/
https://www.motioncontroltips.com/
https://robomechjournal.springeropen.com/

Course Title : Fabric Manufacturing Engineering-ll (Lab)
Course code : TEX3104
Experiment No : 06
Experiment Title : Study on Let off
Mechanism.
Section: 2B, Group: 04
Performed date: 15th
June, 2021 Submitted date: 23th
June, 2021
Submitted To:
Taslima Ahmed Tamanna
Lecturer,
Dept. of TE
BUFT
Submitted By:
191-091-801
191-097-801
191-098-801
191-099-801
191-100-801
Sec: 2 B, Group: 04
Dept. of TE
BUFT

Experiment Name: Study on Let off mechanism.
Introduction:
During each cycle of weaving, the warp sheet has to be released from weaver’s
beam in order that the woven fabric can be rolled up on a cloth roller without
changing the location of the fell of the cloth. This operation is called let-off
mechanism.
We can say it briefly, Let-off is to supply warp thread in the weaving zone at a
predetermined rate. If let-off is not uniform, the fabric shall be uneven with variations
in pick density and firmness. Negative let-off is a mechanism for controlling the
rotation of the beam on a weaving, warp knitting or other fabric forming machine
where the beam is pulled round by the warp against a breaking force applied to the
beam.
In an easy way it is an arrangement to let the warp from the weaver’s beam at
uniform rate thus maintaining the appropriate warp tension throughout the weaving
process.
Types of Let off motion:
Two types of motion can be identified. Such as:
1. Positive let off motion
2. Negative let off motion
Two other types of categories:
1. Mechanical let off
2. Electrical Let off
Objectives:
1. To know about Let off mechanism
2. To know about positive let off mechanism
3. To know construction of the positive let off mechanism
4. To know about negative let off mechanism
5. To know construction of the positive let off mechanism
Construction of Let-off motion :
It consist of a chain wounded around a pulley of weavers beam. One end of chain is
fix to loom frame and other end is in contact to a lever which passes under the warp
sheet.
Lever is provided with small holes for adjusting its position. A weight is position over
the lever and its position is adjusted time to time by the weaver.

Working of Let-off mechanism:
The let – off works by the pulley action of the take up mechanism. When the cloth is
pull forward the warp tension goes on increasing and due to this the let-off
mechanism reverse rotate the warp beam.
As the beam rotates the chain pulls the weight lever. The weight is shifting from right
side to left side to maintain uniform tension. If the tension is not uniform it can call
shuttle trap, variation in PPI and breakage.
Positive Let Off
In this positive let-off mechanism, constant tension can be maintained and any
variation in tension can be detected. So it is used in modern power looms.
Main parts of positive let off:
1. Warp beam
2. Floating back rest
3. Feeler

4. Spring
5. Warm
6. Ratchet
7. Driving rod
8. Collar
9. Reciprocating collar
10. Warm wheel
11. Large beam wheel
12. Adjusting rod
Construction of positive let off mechanism:
The beam turning mechanism is shown in the figure. The beam is driven by ratchet
on a short vertical shaft, which also carries the worm, which drives the worm wheel.
A pinion on the same shaft as the worm wheel drives the large beam wheel, which is
fixed, to one of the beam flanges. A pawl operator turns the ratchet wheel by the
driving rod, which gets motion of the sley sword. Each time the sley comes forward
the oscillating collar is connected to fixed collar & there is engagements of pawl with
ratchet. As the tension in the warp sheet is increased, the floating rest will move
downwards and the rod carrying the fixed collar will move to the right and the rod R1
will move to move the driving rod to the left. This will bring the fixed collar to the
oscillating collar. As a result, the force of imparted oscillating collar and fixed collar is
more. The pawl drives so more ratchet wheel teeth. So the beam motion is more and
more warp is withdrawn to the increased tension.
Negative Let off
Negative let-off is a mechanism for controlling the rotation of the beam on a weaving,
warp knitting or other fabric forming machine where the beam is pulled round by the
warp against a breaking force applied to the beam.

Main parts of negative Let off:
1. Warp Beam.
2. Beam ruffle
3. Chain.
4. Machine frame
5. Weight lever
6. Pivot
7.Weight

Construction of negative let off:
The warp beam ruffle is wrapped around by chain. The one end of the chain is fixed
at. I.e. at the m/c frame whereas the other end is connected to fulcrum med device
to the weight lever, which is pivoted and a dead weight is placed which can be
moved along the length of the weight lever. In this system the tension of the warp is
regulated by the friction between chain and the beam ruffle. The friction is
controlled by dead weight on the weight lever and the distance of deadweight from
the pivot.
Heavier the dead weight and longer the distance of it from the pivot lesser the let-
off. The warp beam dia gradually decreases as weaving proceeds. So it’s
necessary to increase the let-off rate. If the dead weight is kept on the same place,
the let-off rate will remain unchanged. So an experienced worker is required to
change the dead weight gradually with the change of the warp beam dia. As a
result irregular tension occurs and the rate of yarn breakage may increase.
Conclusion:
The let off motion is the secondary motion of weaving which is used to release
the warp yarns from the weavers beam so that weaving can take place. We
know positive let off is used of modern power loom on the other hand negative
let off mechanism is backdated but simple, it can be used for light and medium
weight fabrics.
We learn from this experiment about both of positive and negative let off motion.
It will be much helpful for working in industries practically.
References:
https://textilelearner.net/positive-let-off-motion-in-weaving/
https://textilelearner.net/principle-of-negative-let-off-
mechanism/ https://textilehelp.org/let-off-motion-types-of-let-
off-motion/
http://onlinetextileschool.blogspot.com/2013/09/positive-let-off-
mechanism.html
http://onlinetextileschool.blogspot.com/2013/09/negative-let-
off- mechanism.html

Technology (BUFT)
Experiment No: 07
Experiment Name: Study on Cam setting process of circular knitting machine.
Group: 04 Sec-2B
Lab Report
191-099-801
Date: 02-07-2021 191-100-801

Experiment No: 07
Experiment Name: Study on cam setting process of circular knitting machine.
Introduction:
Circular knitting Machine: The machine where the needles are arranged on a circular cylinder,
which used to create seamless of fabric, by joining the stiches from the needles is called circular
knitting machine. The term circular covers all those weft knitting machines whose needle beds
are arranged in circular cylinders or dials, including latch, spring bearded and very occasionally
compound needle machinery, producing a wide range of fabric structures, garments, hosiery and
depending in a variety of diameters and machine gauges. In circular knitting machine normally
stationary angular cam systems are used for needle and sinker. Here yarn is supplied from cones,
placed either on an integral overhead bobbin stand or on a freestanding creel through tensioners,
stop motions and yarn guide eyes down to the yarn feeder guides. Stationary yarn feeders are
situated at regular intervals around the circumference of the rotating cylinder. By using circular
knitting machine, we can produce jackets, ladies' tops, sports, T-shirts, casual wear, suits, dresses,
swimwear, cardigans etc.
.
FIGURE: Circular Knitting Machine

Types of Circular Knitting Machines:
Double Jersey Machine: Double jersey machines have two sets of needles; one on dial and as
well as on cylinder. There are no sinkers in double jersey machines. This double arrangement of
needles allows the fabric to be manufactured which is twice as thick as the single jersey fabric,
known as double jersey fabric
Rib Double Jersey Machine: In this machine the two sets of needles one on cylinder and one on
dial are placed at right angles with each other. The cylinder being in vertical position and the dial
in horizontal position, allow the two set of needles to be at right angles, which in turn results in
vertical movement of needles on cylinder and horizontal movement of needle on dial.
These two different movements make the rib pattern which can be recognized by checking the
face and back loops as they run along to the course successively but all the loops of a wale are
same.
Interlock Double Jersey Machine: In this type of double jersey machines, the needles on the
cylinder and the dial are placed opposite and alternatively. Interlock machine uses two types of
latch needles instead only one type which is used generally in circular knitting machine.
Single Jersey Machine: As opposed to double jersey machine, the Single jersey machine has only
one cylinder one which one set of needles and sinkers are placed on. The diameter of this cylinder
is generally around 30 inches, which can vary according to the machines type and requirement.
The fabric manufactured on a Single jersey machine is known as “Single jersey fabric”, they have
a plain thickness, almost half if compared to the Double jersey fabric. Both front and back side of
this fabric is visibly different.

Terry Single Jersey Machine: Terry fabrics are manufactured on Terry circular knitting machine
using “Plush knitting technique”. In this technique generally—the one set of sinker loops are
made longer than the ground fabric sinker loops this longer set of sinker loops form the velvet
like pile on the fabric, both the threads, of pile and ground fabric are worked together to give a
stable structure.
Auto Striper Single Jersey Machine: In this circular knitting machine the yarn is fed via an
automated yarn feeder, which is programmable i.e., can be pre-programmed to feed the yarns
in a specified manner to form the required fabric. Due to the feeding automation in this machine
its speed is far greater than the rest of the circular knitting machines.
Jacquard Single Jersey Machine: These are similar to basic knitting machines, incorporated with
an actuator which works to facilitate the movement of needles via a computerized needle
selecting system. This computerized needle selecting system automates the knit, miss and tuck
to knit the jacquard patterns on the fabric.
Cam arrangement: The cams are the mechanical devices which convert the rotary machine
drive into a suitable reciprocating action for the needles or other elements. Cam is the
fundamental elements of knitting. The cams are carefully getting to produce precisely-timed
movement and dwell periods.
Cams are basically two types. These are –
❖ Engineering Cam.
❖ Knitting cam.
The knitting cams are divided in to three groups. These are-
Knit cam
Miss cam
Tuck cam
On weft knitting machines, yarn feeds must move if the cams move, in order to supply yarn at
the knitting point, and if the cam- boxes rotate the yarn packages and tackle must rotate with
them. If, however, the yarn carriers reciprocate as on flat machines their yarn supply packages
may be situated in a suitable stationary position. Knitting cams are attached either individually
or in unit form to a cam - plate and, depending upon machine design, are fixed, exchangeable or
adjustable. At each yarn feed position there is a set of cams (mainly knit cam) consisting of at
least a raising or clearing cam, a stitch or lowering cam, guard cam and an up-throw cam whose

combined effect is to cause a needle to carry out a knitting cycle if required. On circular machines
there is a removable cam section or door so that knitting elements can be replaced.
Objectives:
To know the cam setting process of circular knitting machine.
To know about single jersey and double jersey fabric.
To know about single jersey and double jersey derivatives.
To know about single jersey and double jersey structure.
To know about single jersey and double jersey used.
Apparatus:
➢ Circular Knitting Machine
➢ Cams
➢ Needles
➢ Sinkers
Description:
Single Jersey Derivatives:
Among all weft knitted fabrics, single jersey fabric is the most popular and widely used. Structure
is an important measure for any material, especially for fabrics. Fabric structure plays a vital role
to increase durability and dimensional stability. The structural modifications are used to a very
great extent in designing plain-knit structures by modifying the order of knitting. The plain knit
structures can be modified with the following alternatives.
Knit loop and miss loop

Knit loop and tuck loop
Knit Loop, miss loop and tuck loop.
Weft Loc-knit Design:
Weft lock-knit is a knit-miss single jersey structure. So, one set of needles is used to produce this
structure. The repeat of the structure completes on four courses. Knitting sequence for a repeat
as follows:
1. First course: Knit on all needles.
2. Second course: Miss on all odd number needles and knit on all even number needles.
3. Third course: Similar as first course knit on all needles.
4. Fourth course: Knit on all odd number needles and miss on all even number needles.
Cross Miss Design:
Cross miss is a miss-knit single jersey structure. So, one set of needles are used to produce this
structure. The repeat of the structure completes on two courses. Knitting sequence for a repeat
as follows:
1.First course: Knit on all odd number needles and miss on all even number needles.
2.Second course: Miss on all odd number needles and knit on all even number needles.

Birds Eye or Double Cross Miss:
Bird’s eye is a knit-miss single jersey structure. So, one set of needles are used to produce this
structure. The repeat of the structure completes on four courses. Knitting sequence for a repeat
as follows:
1. First course: Knit on all odd number needles and miss on all even number needles.
2. Second course: Knit on all odd number needles and miss on all even number needles.
Similar as first course.
3. Third course: Miss on all odd number needles and knit on all even number needles.
4. Fourth course: Miss on all odd number needles and knit on all even number needles.
Similar as third course.
Mock Rib Design:
Mock rib is a knit-miss single jersey structure. So, one set of needles are used to produce this
structure. The repeat of the structure completes on two courses. Knitting sequence for a repeat
as follows:
1. First course: Miss on first three needles and knit on second or next three needles.
2. Second course: It is just opposite of the first course i.e., knit on first three needles and
miss on second three needles.

Single Cross Tuck:
Single cross tuck is a knit-tuck single jersey structure. So, one set of needles are used to produce
this structure. The repeat of the structure completes on two courses. Knitting sequence for a
repeat as follows:
1. First course: Knit on all odd number needles and tuck on all even number needles.
2. Second course: It is opposite of the first course i.e., tuck on all odd number needles and
knit on all even number needles.
Double Cross tuck or Polo Pique Design:
Polo pique is a knit-tuck single jersey structure. So, one set of needles are used to produce this
structure. It is a very popular structure to produce cut and sew knit wear. The prominence of the
design appears on the back side of the fabric. The repeat of the structure completes on four
courses. Knitting sequence for a repeat as follows:
2. Second course: Knit on all odd number needles and tuck on all –even number needles,
which is similar as the first course.
3. Third course: Tuck on all odd number needles and knit on all even number needles.
4. Fourth course: Tuck on all odd number needles and knit on all even number needles,
which is similar as the previous third course.

Single Lacoste or Fred Perry Design:
Single Lacoste is a knit-tuck single jersey structure. So, one set of needles are used to produce
this structure. It is also a very popular structure to produce cut and sew knit wear. The
prominence of the design appears on the back side of the fabric. The repeat of the structure
completes on four courses. Knitting sequence for a repeat as follows:
2. Second course: Knit on all needles.
3. Third course: Tuck on all odd number needles and knit on all even number needles, which
is opposite of the first course.
4. Fourth course: Similar as second course knit on all needles.
Double Lactose Design:
Double Lacoste is a tuck-knit single jersey structure. So, one set of needles are used to produce
this structure. It is also a very popular structure to produce cut and sew knitwear. The
prominence of this design near to the single Lacoste fabric. The repeat of the structure
completes on six courses. Knitting sequence for a repeat as follows:

2. Second course: Same as first course i.e., Knit on all odd number needles and tuck on all
even number needles.
3. Third course: Knit on all needles.
4. Fourth course: Tuck on all odd number needles and knit on all even number needles,
which is opposite of the first course.
Simple Crepe Design:
It may be tuck-knit or miss-knit single jersey structure. So one set of needles are used to produce
this structure. The repeat of the structure completes on four courses. Knitting sequence for a
repeat as follows:
1. First course: Tuck on first needle and knit on all rest of the needles.
2. Second course: Tuck on second needle and knit on all rest of the needles.
3. Third course: Tuck on fourth needle and knit on all rest of the needles.
4. Fourth course: Tuck on third needle and knit on all rest of the needles.
Cellular Blister or Popcorn Design:
It is a tuck-knit single jersey structure. So, one set of needles are used to produce the structure.
The prominence of the design appears on the back side of the fabric. The repeat of the structure
completes on eight courses. Knitting sequence for a repeat as follows:

1. First course: Tuck on first two needles and knit on second or next two needles.
2. Second course: Similar as first course.
3. Third course: Similar as first course.
4. Fourth course: Similar as first course i.e., Tuck on first two needles and knit on next two
needles.
5. Fifth course: Knit on first two needles and tuck on second or next two needles.
6. Sixth course: Similar as fifth course.
7. Seventh course: Similar as fifth course.
8. Eighth course: Similar as fifth course i.e., Knit on first two needles and tuck on second two
needles.
Double Jersey Derivatives based on Rib Structure:
A generic name applied to a range of knitted fabrics made on a rib or interlock basis, the
construction of which is often designed to reduce the natural extensibility of the structure. The
term is generally confined to fabrics knitted on machines of E10 gauge or finer and it may be
classified as ether non-jacquard or jacquard double jersey.
Swiss Double Pique:
Double pique is a double jersey fabric made on a rib basis, using a selection of knitted loops and
floats. Double pique is also known as wave nit, rodier, and over nit. The two most important
sequences are known as Swiss double pique and French double pique respectively. Knitting
sequences of Swiss double pique is shown in the following figure:
1. First course: Cylinder needles- all are producing knit loop.
Dial needles- odd number needles produce knit loop and even number needle produce miss
loop.
2. Second course: Cylinder needles- all are producing miss loop.
Dial needles- same as first course.
3. Third course: Cylinder needles- same as first course.

Dial needles – odd number needles produce miss loop and even number needle produce knit
loop.
4. Fourth course: Cylinder needles- all are producing miss loop.
Dial needles- same as third course.
Half cardigan or Royal Rib:
It is a rib-based structure in which a great number of tuck stitches are added to make the fabric
heavy, wide and soft. From the below notation diagram, it is clear that two knitting sequences
are required to produce one repeat of this type of fabric. A special effect is produced when one
half of the cardigan repeat is substituted for a regular 1 x 1 rib structure. The new fabric is called
a “Half Cardigan” and is produced according to the knitting notation system illustrated in the
following figure. One side of the fabric, in this case the reverse side, is produced with tuck stitches
and therefore looks like a “Cardigan”. The loops of the other side acquire a very rounded and
attractive shape which is very typical for this structure.
The Knitting sequence for a repeat as follows:
1. First course: Regular 1×1 rib structure.
2. Second course: Tuck loop formed by the all needles of one bed and knit loop formed by
the all needles of other bed.
Full Cardigan Rib or Polka Rib:
It is another variation of the 1×1 rib structure. In this case, even more tuck stitches are introduced
which makes the fabric wider, heavier, bulkier and less flexible than the half cardigan or the usual
1×1 rib. Contrary to the previous example the full cardigan is symmetric on both sides. From the
below notation diagram, it is clear that two yarns are inserted into the fabric in order to complete
one full course i.e., loops on the one needle bed and loops on the other needle bed. The two
courses which make the “Cardigan” repeat are illustrated in the above needle notation system.
The Knitting sequence for a repeat as follows-

1. First course: Tuck loop formed by the all needles of back bed and knit loop formed by the
all needles of front bed.
2. Second course: Tuck loop formed by the all needles of front bed and knit loop formed by
the all needles of back bed.
Because of the large number of tuck stitches, both Cardigan and Half Cardigan are very bulky, in
comparison with other knit structures. They are sometimes very fashionable and are used for
heavy outerwear such as sweater.
Half Milana Rib:
A weft-knitted rib-based fabric, consisting of one row of 1×1 rib and one row of plain knitting
made on either set of needles. The appearance and characteristics of the fabric are related to the
ratio of the course lengths of first (1) and second (2). The Knitting sequence for a repeat as
follows-
1. First course: Regular 1×1 rib structure.
2. Second course: Plain structure, all needle of one bed is active and needles of other bed is
inactive.

Single Pique or Cross Tuck Interlock:
It was one of the first to be produced, by placing tuck cams in the dial at every third feeder. The
tuck stitches throw the fabric out approximately 15% wider than normal interlock to a
satisfactory finished width of over 60″, they break up the surface uniformity and help to mask
feeder stripiness but they also increase fabric weight.
Single pique is a tuck-knit interlock structure. So, interlock needle gating system is used to
produce this structure. Long and short needles in dial and cylinder, long needles facing short
needles and vice-versa. The repeat of the structure completes on six feeders. Knitting sequence
for a repeat as follows:
1. First feeder: Knit on all short cylinder needles and tuck on all short dial needles.
2. Second feeder: Knit on all long cylinder and dial needles.
3. Third feeder: Knit on all short cylinder and dial needles.
4. Fourth feeder: Knit on all long cylinder needles and tuck on all long dial needles.
5. Fifth feeder: Knit on all short cylinder and dial needles.
6. Sixth feeder: Knit on all long cylinder and dial needles.
Conclusion:
From this experiment we learn about the cam setting process of circular knitting machine, single
jersey and double jersey fabric, single jersey and double jersey derivatives, single jersey and
double jersey structure, single jersey and double jersey used. The main advantage of circular
knitting is the extremely high speeds at which it produces continuous lengths of fabric; thus, it is
a cost-effective production method for bulk products. Here we observed different design by the
variation of cam arrangement. I intend this volition assistance me inwards my hereafter life. Though it is
online class but our course teacher tries her best to partiers so that, we can learn a lot.

Reference:
1. Book: Understanding Textiles for a Merchandiser by Shah Alimujjaman Belal.
2. https://www.xdknitmachinery.com/types-of-knitting-machines/
3. https://www.xdknitmachiner.com/circular-knitting-machines-an-ultimate-guide
4. https://www.textileblog.com/single-jersey-double-jersey-weft-knitted-structures/
5. https://in.pinterest.com/pin/789044797216204656/
6. https://www.onlineclothingstudy.com/2017/06/different-types-of-knitting-
machines.html

Course Title: Fabric Manufacturing Engineering-II (Lab)
Lab Report
Experiment No: 08
Lecturer, BUFT
Department of TE
191-091-801
191-097-801
191-098-801
191-099-801
191-100-801
Group: 04
Sec-2B
Experiment Name: Study on V-bed Knitting Machine

Introduction:
A “Flat” or Vee Bed knitting machine has two flat needle beds having an upside-down “V”
formation. So, It is called “V” bed flat knitting machine. It is a weft knitting machine. According
to Flat bar knitting machine is three type. There are:
1. Flat Bed or V-Bed
2. Single-Bed
3. Unidirectional Bed
In this experiment we also discuss about Flat Bed or V-Bed knitting machine.
Objective:
1. To know about the passage of yarn and fabric of the v-bed knitting machine.
2. To know about the different parts and their functions of the machine.
3. To know about the cam arrangement of the machine.
Description:
Flat-bed knitting machines are traditionally used for the production of pullovers and other
outerwear garments. Compared to other knitting machines, a modern computerized flat-bed
knitting machine has the following main capabilities:
•Individual needle selection. According to the knitting process, needles can be put in and
out of action during the knitting operation.
•Three-way technique. Knit, tuck and miss can be easily realized in the same knitting
course.
•Loop transfer facility. Stitch loops can be easily transferred between two needle beds. A
machine with four needle beds has been developed to realize double knitted structure with
increased facility.
•Loop length change facility. Each loop size can be chosen according to knitting
requirements.
•Holding down sinkers and special take-down systems.

# Figure of V-bed knitting Machine:

#Main parts of v-bed knitting machine:
1. Yarn package
2. Front needle bed
3. Yarn guide
4. Needle spring
5. Tension spring
6. Fabric
7. Cymbal tension
8. Dead weighting system
9. Yarn take-up
10. Latch needle
11. Fabric comb
12. Yarn carrier
13. Back needle bed
Machine description:
In the following figure shows a cross section of a simple hand powered and manipulated V-bed
rib flat machine. The trick walls are replaced at the needle bed verges by fixed, thinner, polished
and specially shaped knock-over bit edges. In rib gating, a knock-over bit in one bed will be
aligned opposite to a needle trick in the other bed. During the edges of the knock-over bits
restrain the sinker loops as they pass between the needles and thus assist in the knocking over
of the old loops and in the formation of the new loops.
The cover plate is a thin metal blade, located in a slot across the top of the needle bed tricks. It
prevents the stems of the needles from pivoting upwards out of the tricks as a result of the fabric
take down tension drawing the needle hooks downwards whilst allowing the needles to slide freely
in their tricks.
Latch opening brushes are attached to the cam plates of both needle beds to ensure that the needle
latches are fully opened. The supports of the brushes are adjustable to ensure precise setting of the
bristles relative to the needles.
The cam-carriage either slides or runs on ball bearings or wheels, along guide rails, one of which
is fixed over the lower end of each needle bed. It is propelled either by hand or from a motor driven
continuous roller chain or rubber belt.
Each yarn carrier is attached to a block which slides along a bar, which, like the carriage guide
rails, passes across the full width of the machine. Two levers are usually provided, one at each end
of the needle bed. One is for racking the back needle bed, to change the gating of the needle beds
for changes of rib set out or rib loop transfer.

#Different Parts identification and their Function:
1. Yarn package:
It is used to supply yarn in machine.
2. Yarn guide:
The yarn is then guided into the knitting zone through the thread guide, which is typically
a small plate with a steel eyelet for the yarn. It is used to maintain the path of yarn.
3. Needle spring:
Function of spring-loaded latch needles 1 The needle latch is spring loaded. It springs
back automatically to the open and closed position, guar-anteing simple knitting-on.
4. Cymbal tension:
It is a spring-loaded tensioning device. It is used to maintain the uniform tension of yarn.
5. Fabric comb and Dead weighting system:
The hole system is used to take -up the fabric from the knitting one. Fabric is taken-up
between the gaps of the two needle.
6. Yarn take-up:
It is used to take-up the yarn From package at a constant rate.:
7. Latch needle:
To produce the loop.
8. Yarn carrier:
Yarn carrier is used to supply yarn to the needle hook.
9. Carrier Rail:
Used for the carrier to move on.

Process Flow Chart of Flat Bed Knitting Section:
The process flowchart of the Flat Bed knitting is as follows:
Sample Collar/ Cuff.
↓
Design & Size analysis.
↓
Machine Selection.
↓
Machine Setting for the Required Design.
↓
Knitting of the collar/ Cuff.
↓
Confirm Required Quality.
↓
Withdraw the Collar/ Cuff and Weighting.
↓
Inspection of the Collar/ Cuff.
↓
Delivery.
Feature of flat knitting machine:
1. 2 stationary needle bed in flat knitting m/c arranged in an inverted V formation
2. Latch needle is used
3. Angular cam of a bi-directional cam system used
4. There is a separate cam system for each needle bed
5. The two cam systems linked together by a bridge, which passes across from one needle
bed to the other
6. Carriage with determined yarn carrier issued
7. Cam system is attached to bottom side of carriage
8. The flat m/c is the most versatile of the weft knitting m/c
9. Fabric produce with finer to coarser yarn
10. The operation and supervision of the m/c is simple
11. The stitch length range is wide and possibly of changing the m/c gauge
12. Trimmings, edging, collars, to shaped panels and integrally knitted complex garments and
other articles

# Different structure name produce by V-bed knitting m/c:
“V-Bed” flat knitting machine produce three type of fabric. There are – (1* 1) Rib, (2*1)
Rib and single jersey tube.
Specification of these Fabric:
1. Fabric Name: (1*1) Rib.
Use cam : Only knit Cam.
Needle arrangement: Alternate/ Cross set up.
Used machine: “V-bed Flat knitting machine.
2. Fabric Name: (2*1) Rib.
Use cam : Only knit Cam.
Needle arrangement: 2/1 set up.
3. Fabric Name: single jersey tube
Use cam : knit Cam and Miss Cam.
Needle arrangement: Alternate/ Cross set up.
Advantages of Flat Knitting Machine:
• Out of all weft knitting machines that are available to us, flatbed knitting machines are
the most versatile.
• These knitting machines offer us with a high stitch potential which includes needles
selection on one or both beds, needle-out designs, racked stitches, tubular knitting,
striping, loop transfer. By making use of flat knitting machines, we can also change the
width of the knitting fabric.
• We can knit a wide range of yarn counts per machine gauge including the number of ends
of yarn in one knitting system by utilizing flatbed machines.
• These machines offer us a wide stitch length range, and there is also the possibility of
changing the machine gauge.
• As compared to the other weft knitting machines, the operation as well as supervision of
these knitting machines is effortless and is relatively less arduous.
• These machines help in the production of knitting products like school uniform sweaters,
t-shirts, caps, stoles, mufflers by using different materials including cotton, silk, wool,
polyester to knit different patterns and designs. The number of garments or panels
simultaneously knitted across the machine is dependent upon its knitting width, yarn
carrier arrangement, yarn path and package accommodation.

Application of v-bed flat knitting machine:
Vee-bed flat knitting machines are widely used for the production of sweater, collar-cuff,
etc. This machine describe in details in the following section chapter of sweater knitting.
Knitting of sweater panels (Flat knitting) - Knitters knits sweater panels manually on flat knitting machine as per the
design provided to them. In piece rate production knitting one worker makes all 4/5 panels (front, back, collar and
2 sleeves panels etc.). The number of a sweater panel may increase depending on style. Like a high fashion, a
sweater might have side pockets and belt, front placket. Sweater collar is made in separate knitting machines with
same batch/lot of yarns. Flat knitting machines are available in different gauze setting to produce sweaters for
different weights. Small components like placket and belts are made in automatic knitting machines.
Conclusion:
Finally it can be said that the experiment is very important. By this experiment we may learn how
to change the design, how to operate the machine and how to changing the position of cams to
produce different types of designs which helps us in our practical life.
Reference:
1. Own write.
2. https://www.textileflowchart.com/2015/11/process-flow-chart-of-flat-bed-knitting-section.html
3. https://www.xdknitmachinery.com/types-of-knitting-
machines/#:~:text=Flat%20Bed%20or%20V-
Bed%20Flat%20Knitting%20Machine%20A,to%20move%20the%20knit%2C%20tuck%20and%20
transfer%20stitches.
4. https://www.sciencedirect.com/topics/engineering/flatbed-knitting-machine
5. https://textilelearner.net/v-bed-knitting-machine-parts/
6. http://www2.rgu.ac.uk/subj/ats/TeachingWeb/textiles/knit/k10.htm
7. https://www.fibre2fashion.com/industry-article/1815/three-dimensional-seamless-garment-
knitting

Course Title : Fabric Manufacturing Engineering-ll (Lab)
Course code : TEX3104
Experiment No : 09
Experiment Title : Study on different parts with function and working principle
of Warp knitting m/c
Section: 2B, Group: 04
Performed date: 29th
June, 2021
Submitted date: 06th
July, 2021
Submitted To:
Taslima Ahmed Tamanna
Lecturer,
Dept. of TE
BUFT
Submitted By:
191-091-801
191-097-801
191-098-801
191-099-801
191-100-801
Sec: 2 B, Group: 04
Dept. of TE
BUFT

Experiment Name: Study on different parts with function and working principle
of Warp knitting m/c
Introduction:
Warp knitting is a family of knitting methods in which the yarn zigzags along the length
of the fabric; i.e., following adjacent columns, or wales, of knitting, rather than a single
row, or course. For comparison, knitting across the width of the fabric is called weft
knitting.Since warp knitting requires that the number of separate strands of yarn, or
ends, equals the number of stitches in a row, warp knitting is almost always done by
machine rather than by hand.
And which machine is used for warp knitting is called warp knitting machine
Objectives:
* To know about basic warp knitting machine.
* To know about different types of warp knitting machine.
* To know about different parts of the machines
* To know about their working principle.
Different types of warp knitting machine
Warp knitting machine is one kind of flat bed machine. This machine produces the
knitted loops in wales direction. There are two major classes of warp knitting machine.
They are the ‘Tricot’ & the ‘Raschel’ warp knitting machine.

Tricot warp knitting machine
The ‘Tricot’ warp knitting machine is also termed as automatic warp knitting of its
function.
Main parts of the machine:
1. Compound needle
2. Pattern chain
3.Needle bar
4.Guide bar
5.Pattern drum
6.Main shaft
7.shinker & shinker bar
8. Intermediate shaft
9.sliding latch
10. Let off mechanism
11. Sliding latch bar
12. Take up mechanism
13. Comb
14. Machine A/C
15.Cloth roller
16. Toothed belt
17. link
18. Warp beam
19. Rocker shaft

Here are the key objectives of studying the tappet shedding mechanism:1. To understand how tappet shedding works to separate the warp yarns into two layers (sheds). 2. To identify the main components of the tappet shedding system - tappets, heald shafts, healds.3. To observe how the tappets lift and lower the heald shafts in sequence to form an open shed.4. To understand the relationship between the tappet cam profile and the motion of the heald shafts. 5. To learn how changing the tappet cam profile can affect the shed formation and weaving pattern

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