FIELD OF THE INVENTION
[0001] The present invention relates to textile machines, particularly the invention relates
to broken yarn lifting arrangement to detach the broken yarn end from the spinning
cop to enable automatic piecing operation in textile ring spinning machines.
BACKGROUND OF THE INVENTION
[0002] Ring spinning machines are the most crucial machines in textile spinning mills. The
said ring spinning machines delivers the final stage of cotton in spinning line, so
called yarn. During ring spinning, yarn breakage occurs frequently, and it is to be
continuously monitored and pieced by the manual labours. The yarn breakage occurs
due to various parameters of yarn and machine and it is unavoidable. The broken yarn
thread normally tangles with the wound yarn in the cop at any portion from top to
bottom of the cop which cannot be adjudged precisely. In long spinning frame sites,
manual labours continuously watch for yarn breakages and perform manual piecing of
broken yarns. This has to be done for a machine frame normally consisting of more
than 1600 spindles. Then, yarn spinning sequence has to be restarted then and there
after yarn breakage in order to resume yarn spinning and to avoid wastage of yarn.
[0003] To overcome above problems, automatic piecing units are developed. The automatic
piecing unit is in the form of a movable vehicle with wheels/rails. The said piecing
vehicle stops at respective spindle units which require piecing attention. The piecing
unit in general moves longitudinally over the machine frame aisles. Before initiating
piecing operation, the piecing vehicle stops in front of the spindle position of ring
spinning machine. Then the broken yarn end which is available in the spinning cop
has to be found and detached from the cop and lifted above to enable piecing operation.
The said detaching of yarn from spinning cop is not successfully done so far in any
known type of automatic piecing units.
[0004] The present invention provides an improved arrangement for detaching the broken yarn
end from the spinning cop to enable automatic piecing in ring spinning machines.
OBJECTIVE OF THE INVENTION
[0005] These objectives are provided to introduce a selection of concepts in a simplified
form that are further described below in the detailed description. This objective
are not intended to identify key features or essential features of the claimed subject
matter, nor is it intended to be used as an aid in determining the scope of the claimed
subject matter.
[0006] The main object of the present invention is to provide an improved piecing unit for
textile ring spinning machines.
[0007] Another object of the present invention is to provide a yarn lifting arrangement
in the automatic piecing unit of the textile ring spinning machines.
[0008] Yet another object of the present invention is to provide an improved broken yarn
end detaching arrangement in the automatic piecing unit of the textile ring spinning
machines.
SUMMARY OF THE INVENTION
[0009] According to the invention, the automatic piecing unit is provided for textile ring
spinning machines. The automatic piecing unit assists in yarn piecing operation during
yarn breakage incidents in ring spinning machines. The proper picking / detaching
of the broken yarn end from the spinning cop is necessary for the successful piecing
of the broken yarn ends. To enable detaching of the broken yarn end, the present invention
is provided with a yarn lifting arrangement in the automatic piecing unit. The lifting
arrangement is placed in front of the ring rail slightly below the ring rail position
such that it purges air towards the cop from plurality of orifices for lifting the
broken yarn end from the cop. The jet members are provided around the spinning cop
at the bottom portion of the cop preferably. The lifting arrangement is advantageously
placed at any position in front of the cop from top to bottom as an embodiment. Then
the detached yarn end is moved upwards into a controlled suction nozzle adjacent to
the drafting unit to hold the yarn until piecing said yarn with the roving material
delivering from drafting zone.
[0010] According to an aspect of the invention, a yarn lifting arrangement for an automatic
yarn piecing unit, comprising of a base plate having a first end and a second end.
The first end connected to an actuating means provides said base plate working position
in the forward motion and home position in the backward motion. The second end is
a free end having an opening near to the free end configured to encircle a cop of
a spindle in the working position. Said yarn lifting arrangement further comprises
plurality of jet members with plurality of orifices configured to position around
the contour of the opening, supplying air current when the base plate is in working
position to detach the tangled yarn end from the spinning cop and to lift the yarn
upwards to enable yarn piecing in the textile machine.
[0011] According to another aspect of the invention, a method for lifting a yarn by a piecing
unit, comprising the steps of, placing plurality of jet members around the contour
of the opening of a base plate such that plurality of orifices projects to a cop of
a spindle, applying and relieving spindle brake for a predetermined time, supplying
air current through said plurality of jet members through the plurality of orifices
for a predetermined time, and detaching the tangled yarn end from the cop through
the air current from said jet members and lifting the yarn upwards to enable yarn
piecing in textile machine.
[0012] Other aspects and advantages of the invention will become apparent from the following
description, taken in conjunction with the accompanying drawing, illustrating by way
of example the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] For a more detailed understanding of this invention, reference is made to the accompanying
drawings in which:
Figure 1 illustrates the schematic view of the yarn lifting arrangement, according
to the present invention;
Figures 2A and 2B illustrates the schematic views of the yarn lifting arrangement
in home position and working position, according to an embodiment of the present invention;
Figure 3A illustrates the side view of the yarn lifting arrangement in which broken
yarn is to be lifted, and figure 3B illustrates broken yarn lifted, according to the
present invention; and
Figures 4 illustrates the schematic view of a jet member, figure 4A illustrates the
top view of a jet member, and figure 4B illustrates the cross-sectional view of a
jet member, according to the present invention.
[0014] Persons skilled in the art will appreciate that elements in the figures are illustrated
for simplicity and clarity and may have not been drawn to scale. For example, the
dimensions of some of the elements in the figure may be exaggerated relative to other
elements to help to improve understanding of various exemplary embodiments of the
present disclosure.
[0015] Throughout the drawings, it should be noted that like reference numbers are used
to depict the same or similar elements, and features.
DETAILED DESCRIPTION OF THE INVENTION
[0016] The following description with reference to the accompanying drawings is provided
to assist in a comprehensive understanding of exemplary embodiments of the invention
as defined by the claims and their equivalents. It includes various specific details
to assist in that understanding but these are to be regarded as merely exemplary.
Accordingly, those of ordinary skill in the art will recognize that various changes
and modifications of the embodiments described herein can be made without departing
from the scope and spirit of the invention. In addition, descriptions of well-known
functions and constructions are omitted for clarity and conciseness.
[0017] Automatic piecing unit is provided for textile ring spinning machines. The automatic
piecing unit moves longitudinally along the aisle of the ring spinning machine. The
ring spinning machine is capable of winding yarn onto a bobbin mounted to spinning
spindle, so called cop. When yarn breakage occurs in the spinning sequence, the broken
yarn thread is tangled in the spinning cop. To enable yarn piecing, the tangled yarn
end has to be detached from the cop. Thus, automatic piecing unit assists in yarn
piecing operation during yarn breakage incidents in ring spinning machines. The proper
picking / detaching of the broken yarn end from the spinning cop is necessary for
the successful piecing of the broken yarn ends. To enable the detaching of the broken
yarn end, the present invention is provided with a yarn lifting arrangement in the
automatic piecing unit.
[0018] Figures 1 and 2 illustrates the schematic view of the yarn lifting arrangement, according
to the present invention. Accordingly, a yarn lifting arrangement (102) for an automatic
yarn piecing unit (100), comprising of a base plate (104) having a first end and a
second end. The first end connected to an actuating means (106) provides the base
plate (104) working position in the forward motion and home position in the backward
motion. The actuating means (106) is at least a pneumatic piston - cylinder actuator
preferably or the like. The second end is a free end having an opening near to the
free end configured to encircle a cop (110) of a spindle (112) in the working position.
In a preferred embodiment said opening is in semicircular shape. Said yarn lifting
arrangement (102) further comprises plurality of jet members (108) configured to position
around the contour of the opening, supplying air current in the working position to
detach the tangled yarn end from the spinning cop (110) and to lift the yarn upwards
towards the drafting zone to enable effective automatic yarn piecing in the textile
machine. The corresponding figure 3A illustrates the side view of the yarn lifting
arrangement in the automatic piecing unit and winding cop of ring spinning machine
in which broken yarn is to be lifted, and figure 3B illustrates broken yarn is lifted
and sucked upwards into the top suction unit in front of the drafting zone of the
ring spinning machine, according to the present invention.
[0019] The jet member (108) is a block having plurality of orifices (118B) on the tapered
surface formed at an acute angle between the top face and the side facing said cop.
The air purging hole of the orifices (118B) of the jet members (108) forms an acute
angle with respect to the vertical. According to an embodiment of the invention, the
acute angle between the orifice (118B) and the vertical is in the range of 15 degrees
to 30 degrees, preferably 20 degrees. The diameter of the orifice (118B) is preferably
2mm. The block has a through hole (118A) along the horizontal axis parallel to line
of position of the plurality of orifices (118B) such that air from a suction source
is transferred to plurality of orifices (118B) through hole (118A). The block can
also be provided with hole along the horizontal axis perpendicular to line of position
of the plurality of orifices (118B). Figures 4 illustrates the schematic view of a
jet member, and the corresponding figures 4A, 4B illustrates the top view and cross-sectional
view the of a jet member.
[0020] In a preferred embodiment, the number of jet members (108) in a yarn lifting arrangement
(102) can be three. The jet members can also be a common unit according to an embodiment.
The jet members are positioned on the contour of the opening at an included angle
of 90 degrees between them. The first jet member (108B) is placed in front of the
spinning cop in substantially parallel manner to the length of the ring spinning frame.
The second and third jet members (108A, 108C) are placed in substantially perpendicular
manner to the length of the ring spinning frame, one each at the sides of the spinning
cop. According to the invention, each of the jet members (108A, 108B, 108C) are provided
with plurality of orifices (118B) preferably three.
[0021] In the process of yarn lifting, the yarn lifting arrangement (102) is actuated to
move forward to reach working position in which jet members (108) are positioned concentrically
around the cop (110) of the spindle (112) in front of the ring rail of ring spinning
machine (not shown) slightly below the ring rail position. In the next step, the cop
(110) placed in the ring spinning spindle (112) is purged with air from the jet members
(108). Thus, the broken yarn (116) end is lifted from the cop (110) and caught into
the suction unit (114) which is provided with controlled suction so as to not unwind
the already wound cop (110). Then the detached yarn end (112) is moved upwards into
a controlled suction nozzle adjacent to the drafting unit to hold the yarn until piecing
said yarn with the drafted roving material delivering from drafting zone.
[0022] According to an example embodiment of the invention, the jet members are worked in
the following sequence to achieve successful detaching and lifting of the broken yarn
end from the spinning cop. The jet members are positioned at a predetermined distance
from spindle centre, along the contour of the opening. When the spindle brake (not
shown) is applied for a predetermined period in the range of 0.1 to 1 second, for
example 0.7 seconds, spindle stops rotating. During that time, the second and third
jet members (side jets) are made to purge air jets through the plurality of orifices
for a fraction of second in the range of 0.01 to 0.1 seconds, for example 0.05 seconds.
Subsequently, spindle brake is relieved for a predetermined period in the range of
0.1 to 0.5 seconds, for example 0.2 seconds, rotating the spindle. During that time,
the first jet member is made to purge air jet through the multiple / plurality of
orifices for a fraction of second in the range of 0.01 to 0.1 seconds, for example
0.05 seconds. As a result of above said sequences, the broken yarn end is detached
from the spinning cop irrespective of its position anywhere from top to bottom and
directed upwards towards the drafting zone successfully. The yarn end detached and
directed upwards by the action of the jet members are sucked by another controlled
suction unit placed at the top of the automatic piecing unit in front of the drafting
zone of the ring spinning machine (not shown). Thereby, the broken yarn is lifted
to enable automatic piecing with the drafted material.
[0023] According to another example embodiment, the jet members are worked in the following
sequence to achieve successful detaching and lifting of the broken yarn end from the
spinning cop. Initially, the jet members are placed at a predetermined distance from
spindle centre along the contour of the opening. The first jet member purges air jet
when the spindle is applied brake for a predetermined time interval. Then, the spindle
brake is relieved for a predetermined time interval in fraction of second. During
that time, the second and third jet members purges air jet. As a result of the above
said action, the broken yarn end is detached from the spinning cop and directed upwards
to enable automatic piecing with the drafted material. The above sequence takes place
irrespective of the ring rail position. The above sequences are example embodiments
only. The three jet members are worked in any different sequences and any different
time intervals. The jet members are not defined to three in total, it may also be
more than three or less than three.
[0024] Generally, the lifting arrangement is placed in front of the ring rail slightly below
the ring rail position such that it purges air towards the cop from plurality of orifices
for lifting the broken yarn end from the cop. The lifting arrangement can be advantageously
placed at any position in front of the cop from top to bottom as an embodiment. In
a preferred embodiment, the lifting arrangement is positioned at the bottom portion
of the spinning cop. Thus, the above described automatic piecing unit for ring spinning
machine frame provides an effective broken yarn end lifting arrangement.
[0025] For exemplary the embodiment of this invention employs yarn lifting arrangement for
an automatic yarn piecing unit. Various modifications to these embodiments are apparent
to those skilled in the art from the description and drawings herein. Therefore, the
description is not intended to be limited to the embodiment shown along with the accompanying
drawings but is to be provided broadest scope consistent with the principles and novel
and inventive features describe/disclosed or suggested herein. Any modifications,
equivalent substitutions, improvements etc. within the spirit and principle of the
present invention shall all be included in the scope of protection of the present
invention.
1. A yarn lifting arrangement for a yarn piecing unit, comprising of:
a base plate having a first end and a second end,
said first end connected to an actuating means provides said base plate working position
in the forward motion and home position in the backward motion,
said second end is a free end having an opening near to the free end configured to
encircle a cop of a spindle in working position; and
plurality of jet members with plurality of orifices, configured to position around
the contour of the opening, supplying air current when the base plate is in working
position to detach the tangled yarn end from the spinning cop and to lift the yarn
upwards to enable yarn piecing in the textile machine.
2. The yarn lifting arrangement as claimed in claim 1, wherein said jet member is a block
having plurality of orifices on the tapered surface, said orifices forms an acute
angle with respect to the vertical, and the block has a through hole along the horizontal
axis parallel and/or perpendicular to line of position of the plurality of orifices
such that air from a suction source is transferred to plurality of orifices through
hole.
3. The yarn lifting arrangement as claimed in claim 2, wherein said acute angle is in
the range of 15 degrees to 30 degrees.
4. The yarn lifting arrangement as claimed in any of the preceding claims, wherein the
number of jet members is three.
5. The yarn lifting arrangement as claimed in any of the preceding claims, wherein the
number of orifices in the jet member is three.
6. The yarn lifting arrangement as claimed in claim 4, wherein the jet members are positioned
on the contour of the opening of base plate with an included angle of 90 degrees between
them.
7. The yarn lifting arrangement as claimed in claim 1, wherein said actuating means is
a pneumatic piston - cylinder actuator.
8. The yarn lifting arrangement as claimed in claim 1, wherein at least two jet members
are provided with air current initially and the third jet member is provided with
air current after a predetermined time interval to lift the yarn upwards.
9. The yarn lifting arrangement as claimed in claim 1, wherein at least a jet member
is provided with air current initially and the other jet members are provided with
air current after a predetermined time interval to lift the yarn upwards.
10. The yarn lifting arrangement as claimed in claim 1, wherein the plurality of jet members
are provided with air currents one by one at predetermined time intervals to lift
the yarn upwards.
11. The yarn lifting arrangement as claimed in claim 1, wherein said jet members are provided
with air current for predetermined time and said air current is provided and stopped
intermittently.
12. The yarn lifting arrangement as claimed in claim 1, wherein said jet members are provided
with air current when spindle brake is applied for a predetermined time.
13. The yarn lifting arrangement as claimed in claim 1, wherein said jet members are provided
with air current when spindle brake is relieved for a predetermined time.
14. A method for lifting a yarn by a piecing unit, the method comprising;
placing plurality of jet members around the contour of the opening of a base plate
such that plurality of orifices projects to a cop of a spindle;
applying and relieving spindle brake for a predetermined time;
supplying air current through said plurality of jet members through the plurality
of orifices for a predetermined time; and
detaching the tangled yarn end from the cop through the air current from said jet
members and lifting the yarn upwards to enable yarn piecing in textile machine.
15. The method of yarn lifting as claimed in claim 14, wherein at least two jet members
are provided with air current initially and the third jet member is provided with
air current after a predetermined time interval to lift the yarn upwards.
16. The method of yarn lifting as claimed in claim 14, wherein at least a jet member is
provided with air current initially and the other jet members are provided with air
current after a predetermined time interval to lift the yarn upwards.
17. The method of yarn lifting as claimed in claim 14, wherein the plurality of jet members
are provided with air currents one by one at predetermined time intervals to lift
the yarn upwards.