Showing posts with label F. Experiment. Show all posts
Showing posts with label F. Experiment. Show all posts
30 December 2012
Study on over picking mechanism // How to Increase PPM
Experiment name: Study on over picking mechanism.
Introduction:
Picking is the second primary motion in weaving. The action of inserting weft yarn through the warp yarns is called picking.
Introduction:
Picking is the second primary motion in weaving. The action of inserting weft yarn through the warp yarns is called picking.
The functions of picking mechanism are:
1.To deliver the shuttle along the correct flight length.
2.To throw the shuttle at a predetermined speed.
Main Parts:
 |
| Over picking |
- Picking arm
- Picking strap
- Picker
- Bottom shaft
- Picking spindle
- Shuttle
- Picking cam
- Vertical shaft
- Cone
- Bowl
- Angular
- Crank shaft
Features of Over Picking Mechanism:
1.Picking arm is over shuttle.
2.Suitable for narrow loom.
3.Higher picks per minute.
4.Less power required.
5.Works more smoothly.
6.Shortening the picking strap and changing the shape of the cam can increase picking force.
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 consists 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.
How to Increase PPM:
1.By increasing motor speed.
2.By setting the cone stud nearer to the picking tappet.
3.By decreasing the picking strap.
4.By altering the position of picking arm towards the centre of the loom.
5.By decreasing the length of the stroke of picking tappet.
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.
Conclusion:
The over picking motion is negative one; the exact amount of power is required to drive a shuttle. By this experiment we learned about the over picking mechanism and how it works. This experience will help us in our future practical life.
1.Picking arm is over shuttle.
2.Suitable for narrow loom.
3.Higher picks per minute.
4.Less power required.
5.Works more smoothly.
6.Shortening the picking strap and changing the shape of the cam can increase picking force.
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 consists 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.
How to Increase PPM:
1.By increasing motor speed.
2.By setting the cone stud nearer to the picking tappet.
3.By decreasing the picking strap.
4.By altering the position of picking arm towards the centre of the loom.
5.By decreasing the length of the stroke of picking tappet.
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.
Conclusion:
The over picking motion is negative one; the exact amount of power is required to drive a shuttle. By this experiment we learned about the over picking mechanism and how it works. This experience will help us in our future practical life.
23 September 2012
Study on under picking mechanism.
Experiment name: Study on under picking mechanism.
Introduction:
Picking is the second primary motion in weaving. The action of inserting weft yarn through the warp yarns is called picking.
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 picking arm. Under picking is controlled by picking cam which is fixed on the bottom shaft. At first the motion comes from motor and m/c 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 fro 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.
How to increase PPM:
1.By increasing motor seed.
2.By increasing the nose shape of picking tappet.
3.By decreasing the length of picking arm.
Uses:
This mechanism is used in all non-automatic cotton looms. It is also used in jute looms.
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.
Introduction:
Picking is the second primary motion in weaving. The action of inserting weft yarn through the warp yarns is called picking.
The functions of picking mechanism are:
1.To deliver the shuttle along the correct flight length.
2.To throw the shuttle at a predetermined speed.
Main parts:
1.Picking arm
1.To deliver the shuttle along the correct flight length.
2.To throw the shuttle at a predetermined speed.
Main parts:
1.Picking arm
2.Picker
3.Picking cam
4.Picking bowl
5.Race board 6.Shuttle
7.Bottom shaft
8.Treadle lever
9.Angular lever
10.Crank shaft
3.Picking cam
4.Picking bowl
5.Race board 6.Shuttle
7.Bottom shaft
8.Treadle lever
9.Angular lever
10.Crank shaft
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 picking arm. Under picking is controlled by picking cam which is fixed on the bottom shaft. At first the motion comes from motor and m/c 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 fro 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.
How to increase PPM:
1.By increasing motor seed.
2.By increasing the nose shape of picking tappet.
3.By decreasing the length of picking arm.
Uses:
This mechanism is used in all non-automatic cotton looms. It is also used in jute looms.
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.
7 January 2012
Analysis of woven fabric(Diamond)
Experiment name: Analysis of woven fabric(Diamond).
Apparatus:
1. Counting glass,
2. Needle,
3. Beesleys balance,
4. Twist tester,
5. GSM cutter,
6. Graph paper.
Analysis:
1. Weave plan: In graph the gaps between the lines are considered according to X axis as weft threads and according to Y axis as warp threads. The up threads are indicated by filling up the gaps and down threads without filling up the gaps.
2. Drafting plan: According to British system drafting plan is drawn at the top of weave plan. Here pointed draft is used to draft the plan.
3. Lifting plan: The lifting plan is drawn at the right side of the weave plan.
4. Face side and backside: The face and backside can be easily understood.
5. Direction of warp and weft: Direction of both warp and weft are indicated by arrow marks by the side of the sample.
6. Raw material: Both warp and weft yarns are cotton.
Object:
1.To sketch the structure of fabric.
2.To know about the raw material of fabric.
3.To know about different specifications of fabric.
Sample:
1.To sketch the structure of fabric.
2.To know about the raw material of fabric.
3.To know about different specifications of fabric.
Sample:
1. Counting glass,
2. Needle,
3. Beesleys balance,
4. Twist tester,
5. GSM cutter,
6. Graph paper.
Analysis:
1. Weave plan: In graph the gaps between the lines are considered according to X axis as weft threads and according to Y axis as warp threads. The up threads are indicated by filling up the gaps and down threads without filling up the gaps.
2. Drafting plan: According to British system drafting plan is drawn at the top of weave plan. Here pointed draft is used to draft the plan.
3. Lifting plan: The lifting plan is drawn at the right side of the weave plan.
4. Face side and backside: The face and backside can be easily understood.
5. Direction of warp and weft: Direction of both warp and weft are indicated by arrow marks by the side of the sample.
6. Raw material: Both warp and weft yarns are cotton.
7. Thread density:
No. of reading
|
EPI
|
Average
|
PPI
|
Average
|
1
|
56
|
54
|
39
|
40
|
2
|
55
|
40
| ||
3
|
53
|
37
| ||
4
|
54
|
38
| ||
5
|
52
|
41
|
8. Yarn count:
No. of reading
|
Warp count
|
Average
|
Weft count
|
Average
|
1
|
18
|
20
|
7
|
9
|
2
|
19
|
10
| ||
3
|
21
|
9
| ||
4
|
20
|
8
| ||
5
|
22
|
11
|
9. Yarn twist:
No. of reading
|
Warp twist
|
Average
|
Weft twist
|
Average
|
1
|
3
|
4
|
3
|
5
|
2
|
5
|
6
| ||
3
|
4
|
4
| ||
4
|
3
|
5
| ||
5
|
6
|
6
|
10. Direction of twist: Both warp and weft yarns are ‘Z’ twisted.
11. Design of fabric: The formula number of this fabric is .
12. GSM calculation: We take one square inch fabric sample and find its weight 0.1116 gm.
We know 1 inch = 2.54 cm i.e. 0.0254 m. So, 1 sq. inch = 0.02542 sq. m.
Now, 0.02542 sq. m sample wt. = 0.1116 gm.
1 sq. m sample wt. = 173 gm.
Therefore GSM of fabric is 267 gm/meter2.
13. Repeat size: The repeat size of this fabric is 18´18.
14. Type of loom: Tappet loom is used to produce this fabric.
End Use:
11. Design of fabric: The formula number of this fabric is .
12. GSM calculation: We take one square inch fabric sample and find its weight 0.1116 gm.
We know 1 inch = 2.54 cm i.e. 0.0254 m. So, 1 sq. inch = 0.02542 sq. m.
Now, 0.02542 sq. m sample wt. = 0.1116 gm.
1 sq. m sample wt. = 173 gm.
Therefore GSM of fabric is 267 gm/meter2.
13. Repeat size: The repeat size of this fabric is 18´18.
14. Type of loom: Tappet loom is used to produce this fabric.
End Use:
This type of fabric is used for making towel, bedsheet, pillow cover, table cloth and so on.
Conclusion:
Conclusion:
Analysis
of fabric structure is very essential to know about the fabric. Because
it gives all kinds of information about the fabric that is needed to
reproduce or to change structure or design of fabric. By this practical I
learn how to analyse primarily a simple plain structure of woven fabric.
http://textilelearner.blogspot.com/
http://textilelearner.blogspot.com/
13 December 2011
STUDY ON POSITIVE LET-OFF MOTION.
EXPERIMENT NAME: STUDY ON POSITIVE LET-OFF MOTION.
INTRODUCTION:
A mechanism controlling the rotation of the beam on a weaving, warp knitting or other fabric is forming machine where the beam is driven mechanically.
MAIN PARTS:
1. Warp beam
2. Floating back rest
3. Feeler
4. Spring
5. Warm
6. Ratchet 7. Driving rod
8.Collar
9.Reciprocating collar
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.
CONCLUSIION:
In this mechanism, constant tension can be maintained and any variation in tension can be detected. So it is used in modern power looms.
INTRODUCTION:
A mechanism controlling the rotation of the beam on a weaving, warp knitting or other fabric is forming machine where the beam is driven mechanically.
MAIN PARTS:
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
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.
CONCLUSIION:
In this mechanism, constant tension can be maintained and any variation in tension can be detected. So it is used in modern power looms.
23 November 2011
Study on interlock circular knitting machine.
Name of the Experiment: Study on interlock circular knitting machine.
OBJECTS:
1.To have the idea about an interlock m/c .
2.To know about its working principles.
Introduction:
Interlock structure is a double faced Interlock structure which consists of two 1×1 Interlock structures. These two 1×1 Interlock structures are joined by interlocking sinker loops and thus produce interlock structure. Interlock structure is produce by special cylinder dial circular machines. Double system V-bed flat knitting machine also used to produce interlock structure.
SPECIFICATIONS:
1.Yarn career
2.Break stop motion
3.Yarn guides
4.Dial
5.Cylinder
6.Dial cams
7.Cylinder cams
8.Dial needles
9.Cylinder needles
10.Oiling and air following devices
11.Sensors
12.Take up rollers
13.Batch rollers
14.Motor
15.Belts 16.Clutches
17.Pulleys and gears
http://textilelearner.blogspot.com/2012/01/interlock-circular-knitting-machine.html#ixzz2OGB7HyU0
OBJECTS:
1.To have the idea about an interlock m/c .
2.To know about its working principles.
Introduction:
Interlock structure is a double faced Interlock structure which consists of two 1×1 Interlock structures. These two 1×1 Interlock structures are joined by interlocking sinker loops and thus produce interlock structure. Interlock structure is produce by special cylinder dial circular machines. Double system V-bed flat knitting machine also used to produce interlock structure.
SPECIFICATIONS:
- Machine name: Interlock Circular Knitting Machine.
- Company:- Precision FUKUHARA Works Limited.
- Origin of the machine:- Japan
- Model no. :- V 8ME 42
- Dia of the machine:- 30”.
- Gauge of the machine:- 22
- No of Feeder:- 84
- Serial no:- 1352761.
- Creel Capacity: 84.
- Feeding: Positive.
2.Break stop motion
3.Yarn guides
4.Dial
5.Cylinder
6.Dial cams
7.Cylinder cams
8.Dial needles
9.Cylinder needles
10.Oiling and air following devices
11.Sensors
12.Take up rollers
13.Batch rollers
14.Motor
15.Belts 16.Clutches
17.Pulleys and gears
Machine description:
The machine has two sets of needles on two different beds, one set on cylinder one in the dial bed. These two sets of needles must be exactly opposite to each other.
The machine has two separate cam system in each bed needles of different length called short needles and long needles. Each cam system controls half of the needles in alternate sequences. One cam system controls knitting at one feeder and other ca, system controls at the next feeders. T ale down mechanism is the same as the other Interlock and plain machines mechanism.
Interlock cam system:
In the figure the cylinder and dial camming to produce one course of ordinary interlock fabric which is actually work of two knitting feeders.
The cylinder cam:
A → clearing cam which lifts the needles to clear the old loop
B, C → stitch cam and guard cams respectively both vertically adjustable to control the stitch length.
D → up through to rise the needle whilst dial needle knock over
E, F → guard cam to complete the truck
G, H → guide cam to provide the track for idling needles
The dial system:
1. Raising cam for tuck position only
2, 3. Dial knock over cam
4. Guard cam to compete the truck
5. Auxiliary knock over cam to prevent the dial needle reentering the old loop
6, 7 Guide cams provides the tracks for idling needles
8. Sewing type clearing cam which may occupy the knitting position as shown in feeder 1 or in tuck position at feeder 2.
Machine parts:
The machine has two sets of needles on two different beds, one set on cylinder one in the dial bed. These two sets of needles must be exactly opposite to each other.
The machine has two separate cam system in each bed needles of different length called short needles and long needles. Each cam system controls half of the needles in alternate sequences. One cam system controls knitting at one feeder and other ca, system controls at the next feeders. T ale down mechanism is the same as the other Interlock and plain machines mechanism.
Interlock cam system:
In the figure the cylinder and dial camming to produce one course of ordinary interlock fabric which is actually work of two knitting feeders.
The cylinder cam:
A → clearing cam which lifts the needles to clear the old loop
B, C → stitch cam and guard cams respectively both vertically adjustable to control the stitch length.
D → up through to rise the needle whilst dial needle knock over
E, F → guard cam to complete the truck
G, H → guide cam to provide the track for idling needles
 |
| Cylinder Cam System |
1. Raising cam for tuck position only
2, 3. Dial knock over cam
4. Guard cam to compete the truck
5. Auxiliary knock over cam to prevent the dial needle reentering the old loop
6, 7 Guide cams provides the tracks for idling needles
8. Sewing type clearing cam which may occupy the knitting position as shown in feeder 1 or in tuck position at feeder 2.
Machine parts:
- Yarn career
- Break stop motion
- Yarn guides
- Dial
- Cylinder
- Dial cams
- Cylinder cams
- Dial needles
- Cylinder needles
- Oiling and air following devices
- Sensors
- Take up rollers
- Batch rollers
- Motor
- Belts
- Pulleys and gears Clutches
Knitting action:
Conclusion:
The circular Interlock machine is a very commonly used machine in country to make Interlock knitted fabric. So this experiment has significance in our study life. In this experiment we sketch the yarn path diagram of the machine, show the knitting action, cam system. We point out the various specification of the machine. So the experiment helps us to know more.
Above all the experiment is a successful one.
The circular Interlock machine is a very commonly used machine in country to make Interlock knitted fabric. So this experiment has significance in our study life. In this experiment we sketch the yarn path diagram of the machine, show the knitting action, cam system. We point out the various specification of the machine. So the experiment helps us to know more.
Above all the experiment is a successful one.
http://textilelearner.blogspot.com/2012/01/interlock-circular-knitting-machine.html#ixzz2OGB7HyU0
20 October 2011
Study on over picking mechanism.
Experiment name: Study on over picking mechanism.
Introduction:
Picking is the second primary motion in weaving. The action of inserting weft yarn through the warp yarns is called picking.
Introduction:
Picking is the second primary motion in weaving. The action of inserting weft yarn through the warp yarns is called picking.
The functions of picking mechanism are:
1.To deliver the shuttle along the correct flight length.
2.To throw the shuttle at a predetermined speed.
Main Parts:
|
| Over picking |
- Picking arm
- Picking strap
- Picker
- Bottom shaft
- Picking spindle
- Shuttle
- Picking cam
- Vertical shaft
- Cone
- Bowl
- Angular
- Crank shaft
Features of Over Picking Mechanism:
1.Picking arm is over shuttle.
2.Suitable for narrow loom.
3.Higher picks per minute.
4.Less power required.
5.Works more smoothly.
6.Shortening the picking strap and changing the shape of the cam can increase picking force.
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 consists 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.
How to Increase PPM:
1.By increasing motor speed.
2.By setting the cone stud nearer to the picking tappet.
3.By decreasing the picking strap.
4.By altering the position of picking arm towards the centre of the loom.
5.By decreasing the length of the stroke of picking tappet.
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.
Conclusion:
The over picking motion is negative one; the exact amount of power is required to drive a shuttle. By this experiment we learned about the over picking mechanism and how it works. This experience will help us in our future practical life.
1.Picking arm is over shuttle.
2.Suitable for narrow loom.
3.Higher picks per minute.
4.Less power required.
5.Works more smoothly.
6.Shortening the picking strap and changing the shape of the cam can increase picking force.
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 consists 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.
How to Increase PPM:
1.By increasing motor speed.
2.By setting the cone stud nearer to the picking tappet.
3.By decreasing the picking strap.
4.By altering the position of picking arm towards the centre of the loom.
5.By decreasing the length of the stroke of picking tappet.
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.
Conclusion:
The over picking motion is negative one; the exact amount of power is required to drive a shuttle. By this experiment we learned about the over picking mechanism and how it works. This experience will help us in our future practical life.
21 August 2011
Study on seven wheel take up mechanism (Cotton Weaving).
Experiment name: Study on seven wheel take up mechanism (Cotton Weaving).
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.
Objects:
1.To know about the construction of the mechanism.
2.To know about drive of the take-up motion.
Take up motion:
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.
Types:
(1)According to drive:
(a) Positive take up.
(b)Negative take up.
(2)According to motion of the cloth/Rate of take up:
(a)Continuous
(b)Intermittent
(3)According to drive given to the cloth roller:
(a)Direct drive
(b)Indirect drive
(4)According to number of gear train:
(a)5-Wheel
(b)6-Wheel
(c)7-Wheel
(5)According to brand name:
(a)Sulzer
(b)Pickanol
(c)Toyota
Main parts& Specifications:
1.Sley
2.Sleysword
3.Connecting rod
4.Monkey tail
5.Holding/Catching/Locking pawl.
6.Pulling pawl
7.Rachet Wheel(24)
8.Standard wheel(36). 9.Changewheel(1-Let)
10.Sewing wheel/Pinion(24)
11.Stud/Compound wheel(89)
12.Stud/Compound Pinion(14)
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.
Objects:
1.To know about the construction of the mechanism.
2.To know about drive of the take-up motion.
Take up motion:
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.
Types:
(1)According to drive:
(a) Positive take up.
(b)Negative take up.
(2)According to motion of the cloth/Rate of take up:
(a)Continuous
(b)Intermittent
(3)According to drive given to the cloth roller:
(a)Direct drive
(b)Indirect drive
(4)According to number of gear train:
(a)5-Wheel
(b)6-Wheel
(c)7-Wheel
(5)According to brand name:
(a)Sulzer
(b)Pickanol
(c)Toyota
Main parts& Specifications:
1.Sley
2.Sleysword
3.Connecting rod
4.Monkey tail
5.Holding/Catching/Locking pawl.
6.Pulling pawl
7.Rachet Wheel(24)
8.Standard wheel(36). 9.Changewheel(1-Let)
10.Sewing wheel/Pinion(24)
11.Stud/Compound wheel(89)
12.Stud/Compound Pinion(14)
13.Take up wheel(89)
14.Take up roller(dia:15.5 inch)
15.Cloth roller
Motion Transfer:
Sley sword to connecting rod. Connecting rod to monkey tail. Monkey tail to pawl. Pawl to rochet wheel. Rochet wheel to standard wheel. Standard wheel to change wheel. Change wheel to 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:
This positive take-up mechanism consists of seven wheels. These are
i)Rachet,
ii)Standard wheel,
iii)Change pinion,
iv)Stud pinion,
v)Stud wheel,
vi)Swing pinion and
vii)Take-up roller wheel.
The
motion is primarily imparted from the sleysword. The sleysword 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 sleysword 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.
Advantages of 7 take-up wheel over 5 wheel take-up mechanism:
1.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,
2.It can give even a fraction of a pick per inch in cloth and
3.The number of teeth in the change wheel and the number of picks per quarter-inch has been simplified.
Remarks:
By this experiment we know about how to cloth is collected by take up mechanism. This is an interesting experiment too. We hope this will be very helpful in our practica life.
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.
Advantages of 7 take-up wheel over 5 wheel take-up mechanism:
1.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,
2.It can give even a fraction of a pick per inch in cloth and
3.The number of teeth in the change wheel and the number of picks per quarter-inch has been simplified.
Remarks:
By this experiment we know about how to cloth is collected by take up mechanism. This is an interesting experiment too. We hope this will be very helpful in our practica life.
3 August 2011
Experiment name: Study on Jacquard shedding mechanism.
Introduction:
In weaving if we want to make any design in our fabric we have to separate the warp yarn according to our weave plan. In tappet or dobby shedding we have some limitations in shedding for a critical design. But in jacquard shedding it can be done easily. Jacquard is a shedding device placed on the top of the loom to produce large no of patterns by using a very large no of warp threads separately by means of harness cords, hooks and needles. The figuring capacity of a jacquard is 1800+. It means it can produce design with more than 1800 warp threads by controlling them individually, which is far beyond the capacity of a dobby or tappet loom.
Main parts:
1. Pattern chain.
2. Motor.
3. Pattern cylinder.
4. Needle.
5. Knife.
6. Harness cord.
7. Neck cord. 8.Comber board.
9. Top board
Introduction:
In weaving if we want to make any design in our fabric we have to separate the warp yarn according to our weave plan. In tappet or dobby shedding we have some limitations in shedding for a critical design. But in jacquard shedding it can be done easily. Jacquard is a shedding device placed on the top of the loom to produce large no of patterns by using a very large no of warp threads separately by means of harness cords, hooks and needles. The figuring capacity of a jacquard is 1800+. It means it can produce design with more than 1800 warp threads by controlling them individually, which is far beyond the capacity of a dobby or tappet loom.
Main parts:
1. Pattern chain.
2. Motor.
3. Pattern cylinder.
4. Needle.
5. Knife.
6. Harness cord.
7. Neck cord. 8.Comber board.
9. Top board
10. Hook.
11. Grid bar
12.Dead weight.
13.Spring board.
14.Needle board.
14.Needle board.
Shedding mechanism:
For shedding mechanism here punched card are used which is made according to design. One pattern card is used for one pick. With these pattern cards pattern chain is made which is placed on the pattern cylinder. On each pick pattern cylinder rotates 1/4th of the full rotation in clockwise direction. At the same time it oscillates to and fro forming an arc.
With every 1/4th rotation a new card comes front of the cylinder in the hook side and for the two and fro movement the needles enter inside the holes of the punch card. This selection of entrance inside the punches of the needles is actually done according to design.
If a needle enters in the hole of the card the needle remains stationary in its position. So the needle crank also remains stationary in its position. So for the upward movement of the knife the hooks also goes upward along with the warp threads to form the top line.
But if needle gets no perforation to enter, the hook is pushed to the right and as result the needle crank takes away the hook along with it. So when the corresponding knife goes upward it cannot lift the hook with it. Thus the warp ends of those hook remains fixed in its position and form the bottom line.
After certain time the knife releases two hooks which is lifted to form the top line and due to wrap tension and dead weight the heald eye comes down. Its downward movement is controlled by grid bar. Each needle has a spring push at its right and that spring pushes back the needle when the next card comes.
Conclusion:
By this experiment we learned about the jacquard shedding and how it works. It is the finest of all machines for making the designed woven fabrics that have been invented and far superior in capacity to a dobby or tappet loom.
22 March 2011
Study on compare between single jersey single truck (conventional) and single jersey four truck circular knitting m/c.
Experiment name: Study on compare between single jersey single truck (conventional) and single jersey four truck circular knitting m/c.
Object:
To know about the difference between single jersey single truck and single jersey four truck circular knitting m/c.
To know about modern development of single jersey four truck knitting m/c.
To know about the problematic area of single jersey single truck knitting m/c.
Introduction:
Single jersey circular knitting m/c is a common m/c in knitting industry. More than 70% of knitted fabric is produced in single jersey m/c. In conventional m/c there is only one cam truck. So we can produce only basic single jersey fabric in this m/c. But in modern m/c there is four truck in the cylinder. So we can produce maximum 4 (four) wales in a repeat. To produce more than 4 wales in a repeat we need jacquard mechanism.
Comparison between single jersey single truck (conventional) and single jersey four truck circular knitting m/c:
Subject:
Single jersey single truck (conventional) circular knitting m/c.
Single jersey four truck circular knitting m/c.
Cam truck
1. One truck.
1. Four truck.
Needle
2. Double butt needle.
2. Single butt needle.
Butt position
3. Same position.
3. Different position.
Feed system
4. Negative Feed System.
4. Positive feed System.
Creel System
5. Over head creel.
5. Side creel.
Cam System
6. Open Cam system.
6. Close Cam system.
7. Open knitting m/c.
7. Close knitting m/c.
Take down
8. Conventional.
8. Modern.
Needle gauge
9. Coarser gauge.
9. Fine gauge.
M/c diameter.
10. This m/c is small diameter.
10. This m/c is large diameter.
11. Basic single jersey fabric is produced.
11. Basic single jersey fabric is produced.
Conclusion:
This is very important to know about the difference between single truck and four truck m/c. This is vastly used in knitting industry. So we need knowledge about this m/c.
http://textilelearner.blogspot.com/2012/02/compare-between-single-jersey-single.html#ixzz2OGAaZ5WH
Object:
To know about the difference between single jersey single truck and single jersey four truck circular knitting m/c.
To know about modern development of single jersey four truck knitting m/c.
To know about the problematic area of single jersey single truck knitting m/c.
Introduction:
Single jersey circular knitting m/c is a common m/c in knitting industry. More than 70% of knitted fabric is produced in single jersey m/c. In conventional m/c there is only one cam truck. So we can produce only basic single jersey fabric in this m/c. But in modern m/c there is four truck in the cylinder. So we can produce maximum 4 (four) wales in a repeat. To produce more than 4 wales in a repeat we need jacquard mechanism.
Comparison between single jersey single truck (conventional) and single jersey four truck circular knitting m/c:
Subject:
Single jersey single truck (conventional) circular knitting m/c.
Single jersey four truck circular knitting m/c.
Cam truck
1. One truck.
1. Four truck.
Needle
2. Double butt needle.
2. Single butt needle.
Butt position
3. Same position.
3. Different position.
Feed system
4. Negative Feed System.
4. Positive feed System.
Creel System
5. Over head creel.
5. Side creel.
Cam System
6. Open Cam system.
6. Close Cam system.
7. Open knitting m/c.
7. Close knitting m/c.
Take down
8. Conventional.
8. Modern.
Needle gauge
9. Coarser gauge.
9. Fine gauge.
M/c diameter.
10. This m/c is small diameter.
10. This m/c is large diameter.
11. Basic single jersey fabric is produced.
11. Basic single jersey fabric is produced.
Conclusion:
This is very important to know about the difference between single truck and four truck m/c. This is vastly used in knitting industry. So we need knowledge about this m/c.
http://textilelearner.blogspot.com/2012/02/compare-between-single-jersey-single.html#ixzz2OGAaZ5WH
16 February 2011
Study on Negative Let-Off Mechanism .
Experiment Name: Study on Negative Let-Off Mechanism .
Introduction:
Let-off is to supply warp thread in the weaving zone at a predetermined rate. 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:
1. Warp beam.
2. Beam ruffle.
3. Chain.
4. Machine frame.
5. Weight lever.
6. Pivot.
7. Fulcrum.
8. Weight.
Let-off mechanism:
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 fulcrummed 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:
Negative let-off mechanism is a very simple and manual mechanism. It is suitable for light and medium weight fabrics. It is mainly used in old looms and for weaving of plain cotton fabric.
Introduction:
Let-off is to supply warp thread in the weaving zone at a predetermined rate. 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:
1. Warp beam.
2. Beam ruffle.
3. Chain.
4. Machine frame.
5. Weight lever.
6. Pivot.
7. Fulcrum.
8. Weight.
Let-off mechanism:
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 fulcrummed 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:
Negative let-off mechanism is a very simple and manual mechanism. It is suitable for light and medium weight fabrics. It is mainly used in old looms and for weaving of plain cotton fabric.
25 January 2011
Production Calculation From Loop Length
Production Calculation From Loop Length:
Let us consider a circular Single Jersey knitting machines , having F no of Feeder and N no of needles , is running with a speed of n r.p.m and producing a fabrics of loop length ‘l’ mm .
Hence , no of courses produced in 1 rev. = F
no of courses produced in n ,, = F.n
no of courses produced in 1 min. = F.n
no of courses produced in 1 hr = F.n.60
As loop length in ‘l’ mm and the total no needle are N
Let us consider a circular Single Jersey knitting machines , having F no of Feeder and N no of needles , is running with a speed of n r.p.m and producing a fabrics of loop length ‘l’ mm .
Hence , no of courses produced in 1 rev. = F
no of courses produced in n ,, = F.n
no of courses produced in 1 min. = F.n
no of courses produced in 1 hr = F.n.60
As loop length in ‘l’ mm and the total no needle are N
 |
| Circular knitting machine |
yarn consumed by 1 needle from 1 hr = F.n.60.l mm
yarn consumed by N needle from 1 hr = F.n.60.l.N mm
= F.n.60.l.N/1000 meter
Total yarn consumed by the m/c in 1 hr = F.n.60.l.N/1000 meter
If yarn count is Nm , then the weight of above yarn = F.n.60.l.N/1000.Nm.1000 Kg
For Example:
Problem: Calculate the production for a circular knitting machine whith the given data
Feeder=84
Diameter=30 inch
Gauge=24/inch
Cylinder r.p.m=18
Yarn count=30Ne
Efficiency=90%
Stitch length=2 mm
Solution:
Length of yarn=(3.14×30× 24× 2 ×84× 18× 60 ×24 ×90)/(1000 ×100)
=8860310.32 meter
=8860.31 km
Now, 20Ne=Ne×tex=590.6
So,tex=590.6/20
=29.58
Again,
1 km yarn weight =29.53 gm
8860.31 km yarn weight=(29.53× 8860.31)
=261.64 kg
23 December 2010
Study on Rib Circular knitting machine.
Name of the experiment: Study on Rib Circular knitting machine.
In rib circular knitting m/c, Rib gaiting:
Knitting action:
The knitting action of a circular rib machine is shown in Fig:
1. Clearing: The cylinder and dial needles move out to clear the plain and rib loops formed in the previous cycle.
2. Yarn feeding: The needles are withdrawn into their tricks so that the old loops are covered by the open latches and the new yarn is fed into the open hooks.
3. Knocking Over: The needles are withdrawn into their tricks so that the old loops are cast off and new loops are drawn through them.
Conclusion:
This experiment has significance in our study life. In this experiment we sketch the yarn path diagram of the machine, show the knitting action, cam system. We point out the various specification of the machine.
Introduction
The
structure in which the face and back loop occurs along to the coarse
successively but all the loops of a wale is same is called rib
structure. The circular knitting machine which is used to produce the rib structures is known as rib machine.
Machine specification:
In a dial cylinder rib machine there is one set of needles on the circumference of the vertical cylinder and another set of needles on a horizontal dial. So two sets of needles remain at the right angle with each other. In dial cylinder machines the dial and cylinder rotates but the cam systems with the feeders remain stationary.
The dial needles get its motion from its butt which is placed on the cam truck. This cam truck is formed by different cam placed on a cam plate.
During the rotation of the cylinder, cylinder needles moves vertically and dial needles moves horizontally. Cylinder needles also get its motion from it. There is a cloth tale up roller which also rotates with unison to dial and cylinder and fabric is wound on it.
Machine specification:
- Machine model → cmoan
- Manufacturer → Paolo Orizio
- Made in → Italy
- No of feeders’ → 40
- Cylinder diameter →20”
- Needle gauge → 18 / inch
- Yarn career
- Break stop motion
- Yarn guides
- Dial
- Cylinder
- Dial cams
- Cylinder cams
- Dial needles
- Cylinder needles
- Oiling and air following devices
- Sensors
- Take up rollers
- Batch rollers
- Motor
- Belts
- Pulleys and gears
- Clutches
In a dial cylinder rib machine there is one set of needles on the circumference of the vertical cylinder and another set of needles on a horizontal dial. So two sets of needles remain at the right angle with each other. In dial cylinder machines the dial and cylinder rotates but the cam systems with the feeders remain stationary.
The dial needles get its motion from its butt which is placed on the cam truck. This cam truck is formed by different cam placed on a cam plate.
During the rotation of the cylinder, cylinder needles moves vertically and dial needles moves horizontally. Cylinder needles also get its motion from it. There is a cloth tale up roller which also rotates with unison to dial and cylinder and fabric is wound on it.
In rib circular knitting m/c, Rib gaiting:
The knitting action of a circular rib machine is shown in Fig:
1. Clearing: The cylinder and dial needles move out to clear the plain and rib loops formed in the previous cycle.
2. Yarn feeding: The needles are withdrawn into their tricks so that the old loops are covered by the open latches and the new yarn is fed into the open hooks.
3. Knocking Over: The needles are withdrawn into their tricks so that the old loops are cast off and new loops are drawn through them.
 |
| Fig: Knitting action of rib circular knitting machine |
This experiment has significance in our study life. In this experiment we sketch the yarn path diagram of the machine, show the knitting action, cam system. We point out the various specification of the machine.
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