7 Wheel Take-Up Mechanism.

Experiment Name: -Study on the seven (7) wheel take up mechanism.

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. Ratchet Wheel (24). 
8.Standard wheel(36). 9. Change wheel (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 rodà Connecting rod to monkey tailà Monkey tail to pawlà Pawl to ratchet wheelà Ratchet wheel to standard wheelà Standard wheel to change wheelàChange wheel to sewing wheelà sewing wheel to stud wheelà Stud wheel to stud pinionà Stud pinion to take up wheelà Take up wheel  to take up.

Working principle:

This positive take-up mechanism consists of seven wheels. These are 

    Ratchet. 

    Standard wheel, 

    Change pinion, 

    Stud pinion, 

    Stud wheel, 

    Swing pinion and 

    Take-up roller wheel. 

Fig: seven wheels take-up mechanism.

The motion is primarily imparted from the sleysword. The sleysword 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 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 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.

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.

3. The number of teeth in the change wheel and the number of picks per quarter-inch has been simplified

.

Conclusions:

 

By this experiment we know about how to cloth is collected by take up mechanism. By this experiment we also learn the different wheel of this mechanism. I think this experiment would be very helpful in our future career.