Introduction:
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. For doing this work two types of mechanism is used. One is 5-wheel mechanism and another is 7-wheel mechanism. 5-wheel take up mechanism is used in case of jute weaving. In this article, I will discuss calculation of 5-wheel take up mechanism.
5-Wheel Take-up Mechanism:
Where,
A = Rachet wheel = 50-60T
B = Change wheel = 1/4
C = Stud wheel = 100-120T
D = Stud pinion = 12-18T
E = Take up wheel = 60-100T
F = Take up roller = 15-16″ (circum)
G = Finger
H = Take up lever
M = Pushing pawl
N = Rotating catch
Working Process:
The beam wheel E is set screwed on the beam shaft and its teeth engaged those of stud pinion D which is connected with stud wheel C.
The stud pinion and stud wheel work loosely upon a stud in a slotted bracket, the slot is concentric with the cloth beam F.
In this positive take up motion is primarily imparted from the sley sword. The finger enters into the slot of the take up lever H, which is fulcrumed at I.
A swinging motion is given to the sley sword and this will cause the paw M to drive the rachet wheel A and set the train of wheels in motion.
Rachet wheel is moved the distance of one tooth by the oscillating pawl for every pick.
Thus motion is transferred to the cloth roller from the rachet wheel by means of five wheels.
Calculation of 5-Wheel Take-up Mechanism:
PPI:
For one rev of one teeth of Rachet wheel (A) = 1 pick take up
E C A
No of revolution of A for 1 rev of F = 1 x ….. x ….. x …..
D B F
75 120 50
= 1 x ….. x …… x ……
15 x 15
2000
= ………
x
Pick spacing:
1 x
Pick spacing = ……. = ……..
PPI 2000
B D F
Or Pick spacing = ….. x ….. x ……
C E A
x 15 15
= ……. x ….. x …..
120 75 50
x
= ……….
2000
Loom constant:
Loom constant is obtained by taking the no of teeth in change wheel = 1
E x C x A
Loom constant = …………
D x 1 x F
Loom constant
Hence, PPI = …….....………..
Change wheel
Contraction 1.5% is not added due to using coarse fabric, Jute, Blanket, Canvas fabric.
So, not adding of 1.5% contraction
