IELD OF THE INVENTION
The present invention relates to a drafting arrangement in spinning preparatory
machines and more precisely the invention relates to sliver piecing 5 in drafting unit
present in textile spinning preparatory machine like card, drawframe or carding
machine with drafting unit.
BACKGROUND OF THE INVENTION
10 Carding is one of the most important process in the textile spinning preparatory
machines. Purpose of the carding process is to open the fiber tufts, remove neps
and maintain the fiber parallel and straight. Carding process can also be used to
create blends of different fibers or different colors. Output of carding sliver is
deposited on sliver-can and transported to draw frame, to attain doubling and
15 drafting of sliver for improving the evenness.
With the evolution of new technology as well as huge requirement in synthetic
yarn manufacturing, there has been a development in a combination of carding
machine with drafting unit. This technology eliminates numerous sliver can
20 transportation in spinning mill, and occupies less floor space and also eliminates
intermediate preparatory machines like lap former/comber and achieves a superior
end product quality (i.e sliver). Carding web delivered from associated doffer
roller, is taken off through web calender rollers and then condensed to form fibre
sliver. Final form of sliver is moved further to drawing or stretching unit to apply
25 the required draft on the sliver. After drafting process, the sliver passes through
pair of sliver calender rollers and then deposited in sliver can by using coiler unit.
The bottom drafting rollers and bottom calender roller are driven by suitable drive
of the machine, whereas the top drafting rollers and top calender roller are
frictionally driven with respect to their bottom rollers. If any sliver breakage
30 occurs before drafting unit or coiler unit, it has to be pieced, i.e. the broken end of
sliver has to be inserted into the sliver funnel/coiler pipe to continue the sliver
production process. Likewise, a fresh sliver introduction also requires this piecing/inserting operation during machine start up. In conventional piecing
operation, the top rollers of drawing unit along with top roller of calender rollers
are lifted simultaneously away from the lower rollers set. Then the sliver is taken
manually from card delivery and passed through the bottom drafting rollers and
bottom calender roller. Now this sliver is inserted into the sliver 5 funnel which is
located beneath the calender roller arrangement. Then the sliver is ready to run
with coiling arrangement which stores the sliver in a sliver can as coil form. After
completing the piecing process, top rollers of calender roller and drafting rollers
are closed or loaded to respective bottom rollers and regular process is continued.
10 Herein the top drafting rollers arrangement and top calender roller are mounted in
a common loading arm with hinge arrangement. Due to this common hinge
arrangement, calender rollers can not run without loading the whole drafting
arrangement. Aforesaid piecing method is time consuming since the machine can
run only after loading the drafting and calender roller arrangement. Moreover this
15 process is not user friendly as the machine operator required to twist the leading
end of sliver sharply before introducing into the sliver funnel for completing the
piecing/inserting operation.
One more important function of the said drafting arrangement is autolevelling
20 which is meant for correcting the linear density variations in the delivered sliver
of carding machine by changing draft at 2 over 2 drafting system. Said
autolevelling function measures the thick and thin place of a running sliver and
corrects it for less irregularity subsequently. The known art of self regulating
process, measures the sliver thickness variation before sliver inlet of drawing unit.
25 Based on the measured variation value, the appropriate variable speed drive varies
the speed of back roller of drafting unit and/or web doffing or doffer roller to
achieve desired sliver uniformity. Meanwhile the front roller pair of the drawing
unit rotates at constant delivery speed. i.e., During regulating process, front roller
pair runs at constant speed and remaining drafting rollers runs at variable speed
30 based on sliver thickness / levelling feedback to attain evenness. In this method,
sliver slack occurs between any one of the rollers like back roller of drafting unit,sliver which is an undesirable cause and affects the sliver quality. And also it
affects the transfer efficiency between cylinder and doffer, since the back roller
speed is altered based on sliver thickness / levelling feedback.
5
There has thus been a need to develop a piecing arrangement and levelling
process with user friendliness and high production rate with desirable quality that
would overcome the disadvantages present in the existing machines.
10 OBJECTS OF THE INVENTION
Primary objective of the present invention is to provide a drafting apparatus that
offers a simplified piecing operation and uninterrupted coiler run without loading
drafting roller of textile spinning preparatory machine.
15 Another objective of present invention is to provide a carding machine with
effective regulating drafting unit.
Yet another objective of present invention is to provide user friendliness in
piecing arrangement and improve the quality of sliver web processed in textile
20 spinning preparatory machine.
SUMMARY OF THE INVENTION
The following disclosure presents a simplified summary of the invention in order
to provide a basic understanding of some aspects of the invention. This summary
25 is not an extensive overview of the present invention. It is not intended to identify
the key/critical elements of the invention or to delineate the scope of the
invention. Its sole purpose is to present some concept of the invention in a
simplified form as a prelude to a more detailed description of the invention
presented herein after.
According to the present invention the carding machine is provided with feed
roller; licker-in roller; main cylinder; revolving flats; doffer, crush roller; sliver
guide channel; web calender rollers; at least a guide roller; a drafting roller unit
with plurality of top and bottom rollers; a dedicated loading arrangement / carrier
arm for loading said top rollers; a calender roller unit with a pair 5 of sliver calender
rollers; and a coiler unit with a sliver deposit can; wherein the drafting roller unit
and calender rollers unit are loaded/unloaded irrespective of one another and
therein the delivery roller pair of said drafting roller unit is provided with
autolevelling function. Said autolevelling function is achieved by controlling or
10 regulating the delivery roller pair through a variable speed drive with respect to
running speed of web doffing rollers and/or web calender rollers. The fiber mat
coming out from carding zone is stripped off by doffer roller and the web is
passed between stripper roller with brush and pair of crush rollers. Then the
carded web is passed through sliver guide channel for condensing and the said
15 condensed fiber strand (i.e sliver) is then transferred through pair of web calender
rollers which delivers the consolidated sliver from card. The card sliver is moved
upwardly over guide roller then it enters into a drafting unit. After completion of
draft, the stretched sliver travels into the coiler unit through pair of calender
rollers and trumpet guide or sliver funnel and then into coiler tube to form a sliver
20 coil.
If sliver breakage occurs between calender roller and coiler unit or if any fresh
introduction of sliver is required, the piecing/inserting action has to takes place.
To overcome the prior art disadvantages, according to the present invention, the
25 drafting arrangement and calender roller arrangement are mounted separately
from one another. Said drawing unit for example comprising of 2 over 2 drafting
roller arrangement is mounted in an inclined manner towards the calender roller
pair and coiler unit. The drawing unit may comprise plurality of drafting rollers
like 3 over 3 or 4 over 3 depending on the requirement. Said drafting unit is
30 provided in substantially horizontal or substantially vertical plane with respect to
coiler plate. During sliver piecing, the top roller of the drawing unit is lifted or opened upwardly on a hinge point. Meanwhile the pair of calender rollers runs at
slow speed because of separate mounting. The leading end of broken sliver is
taken by the machine operator who passes it though the opened drafting unit and
introduce the same into the slowly running calender rollers pair. Then the sliver
reaches the funnel beneath, due to calender rollers action and 5 sliver piecing is
completed. Then Loading of top roller can be done while running at lower speed
after sliver is pieced.
The autolevelling control unit is connected to bottom and/or top rollers of drawing
10 unit through variable speed motor. The measured variance signal is transferred to
said control unit and compared with preset or predefined value. If any deviation is
found, control unit passes the corrected signal to variable speed motor. Based on
the signal, the bottom roller of front drafting roller pair speed is varied to finetune
sliver deviation. Meanwhile the remaining rollers like back roller pair of
15 drafting unit, doffer, web doffing and calender roller maintains constant speed to
prevent sliver slackness and possible classimat faults.
Other salient features and advantages of the invention will become apparent to
those skilled in the art from the following detailed description, which, taken in
20 conjunction with the annexed drawings, discloses exemplary embodiments of the
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other aspects, features, and advantages of certain exemplary
25 embodiments of the present invention will be more apparent from the following
description taken in conjunction with the accompanying drawings in which:
Figure-1 shows the carding machine with drafting system according to present
invention.
Figure-2 & 2a shows the opened or unloaded condition of drafting arrangement
before sliver piecing operation according to the present invention.
Figure-3 & 3a shows the closing or loading condition of drafting 5 arrangement
during sliver piecing operation according to the present invention.
Figure-4 shows the regulating drafting unit of the carding machine according to
the present invention.
10
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
15 embodiments of the present disclosure. Throughout the drawings, it should be
noted that like reference numbers are used to depict the same or similar elements,
features, and structures.
DETAILED DESCRIPTION OF THE INVENTION
20 It should be understood at the outset that although illustrative implementations of
the present disclosure are illustrated below, the present invention may be
implemented using any number of techniques, whether currently known or in
existence. The present disclosure should be in no way limited to illustrative
implementations, drawings, and techniques, illustrated below, including the
25 exemplary design and implementation illustrated and described herein, but may be
modified within the scope of equivalents.
Unless otherwise defined, all terms and especially technical and/or scientific
terms, used herein, may be taken to have the same meaning as commonly
30 understood by one having an ordinarily skilled in the art. Reference is made
herein to some “embodiments”. It should be understood that an embodiment is an example of a possible implementation of any features and/or elements presented
in the foregoing claims. Some embodiments have been described for the purpose
of illuminating one or more potential ways in which the specific features and/or
elements of the foregoing claims fulfill the requirements of uniqueness, utility,
and 5 non-obviousness.
The terms and words used in the following description and claims are not limited
to the bibliographical meanings, but, are merely used by the inventor to enable a
clear and consistent understanding of the present disclosure. Accordingly, it
10 should be apparent to those skilled in the art that the following description of
various embodiments of the present disclosure is provided for illustration purpose
only and not for the purpose of limiting the present disclosure as defined by the
appended claims and their equivalents.
15 It is to be understood that the singular forms "a," "an," and "the" include plural
referents unless the context clearly dictates otherwise. Thus, for example, a
reference to "a component surface" includes a reference to one or more of such
surfaces.
20 All terms (including technical and scientific terms) used herein have the same
meaning as commonly understood by one of ordinary skill in the art to which
various embodiments belong. Further, the meaning of terms or words used in the
specification and the claims should not be limited to the literal or commonly
employed sense, but should be construed in accordance with the spirit of the
25 disclosure to most properly describe the present disclosure.
The terminology used herein is for the purpose of describing particular various
embodiments only and is not intended to be limiting of various embodiments. As
used herein, the singular forms "a," "an" and "the" are intended to include the
30 plural forms as well, unless the context clearly indicates otherwise. It will be
further understood that the terms "comprises" and/or "comprising" used herein specify the presence of stated features, integers, steps, operations, members,
components, and/or groups thereof, but do not preclude the presence or addition
of one or more other features, integers, steps, operations, members, components,
and/or groups thereof. Also, Expressions such as "at least one of," when preceding
a list of elements, modify the entire list of elements and 5 do not modify the
individual elements of the list.
According to the present invention, for example a 2 over 2 drafting rollers of
drafting unit in carding machine is shown in Figure-1. Said carding machine is
10 fed with fibre tufts as raw material from blowroom with help of chute feed system
(not shown in fig). Fiber sheet coming out from the chute feed system is supplied
to feeding area (2) which comprises feed roller and feed plate of carding machine.
Fed fibre sheet is opened when it passed between feed roller and licker-in roller
(1). The opened fibers are transferred to carding zone, where these fibers are
15 processed between main cylinder (4) and revolving flats (3). Thin and carded fibre
layer coming out from carding zone is taken off by doffer roller (5). This thin
layer or web is then carried through several rollers like stripper roller (6) with
brush (7) and pair of crush rollers (8&9). Then the web is passed through sliver
guide channel (13) and then pair of web calender rollers (11&12) delivers the
20 condensed sliver (14) from card. The card sliver (14) is further taken upwardly
over guide roller (10) and then enters into drafting unit consisting of back roller
pair and front roller pair. Said back roller pair comprises top roller (15) and
corresponding bottom roller (16), and the front roller pair / delivery roller pair
consists of top roller (17) and bottom roller (18). The draft value according to the
25 present invention is maintained under 4 when using 2 over 2 type drafting unit.
The drawing unit may comprise plurality of drafting rollers like 3 over 3 or 4 over
3 depending on the requirement. After completion of draft, the stretched sliver
enters into coiler unit. Said coiler unit comprises a pair of calender rollers or
calender roller unit (21), a trumpet guide or sliver funnel (19) and a coiler plate
30 (22). Said calendar rollers (21a, 21b) draws the sliver through the sliver funnel
(19) and then to sliver can (23) with the help of coiler pipe (20). The drafting unit according to the invention is provided in substantially horizontal or substantially
vertical plane with respect to coiler plate (22) surface of coiler unit. As shown in
Fig.1, the drafting unit according to an embodiment of the invention is provided at
40° to 70° or preferably at 60° with respect to coiler plate (22) surface.
5
Sliver piecing arrangement in drafting unit of present invention is shown in the
Figure-2. The drafting unit is provided between web doffing calender roller (11
&12) and coiler unit. For example, the drawing unit is arranged inclined
downwards facing the coiler unit. This drawing unit may be provided in
10 horizontal or vertical position according to preferred machine layout. The top
rollers (15, 17) of the drafting unit and top roller of calender roller are mounted
separately. Considering the user friendliness of piecing arrangement, the top
rollers of drafting unit (200) is mounted in a top arm or loading arm (300) which
can be opened or closed with respect to a hinge point (400) as shown in Figure-
15 2a. And optionally a dedicated loading arrangement (500) is provided for loading
/ unloading any one of calender roller pair. At the time of sliver breakage, the top
roller (15 and 17) of the drawing unit (200) is lifted or opened upward in the
direction of arrow shown in the Figure-2a. Meanwhile the pair of calender rollers
(21) and bottom drafting rollers (16, 18) runs at slow speed. While doing piecing
20 operation, the leading end of broken sliver is carried by the machine operator who
passes it though opened drafting unit (200) and introduce the same into the slowly
running calender rollers pair (21a, 21b) and thereby sliver is pulled off through the
funnel (19) due to calender rollers action and sliver piecing/inserting is completed.
Since the calender rollers are in slow running condition, the production of sliver
25 takes place continuously without affecting the normal operation of machine.
After completion of sliver piecing operation, the drafting unit according to present
invention is loaded or closed as shown in Figure-3 and 3a. On completion of
piecing operation, the top roller arm (300) is closed or loaded against bottom
30 rollers (16 and 18) as directed by arrow. During this condition, the top and bottom
drafting rollers (15, 16, 17 and 18) also runs at slow speed. After loading the top rollers on bottom rollers, the machine is switched to run at normal running speed
or high speed as a function of working.
Regulating drafting unit (200) of carding machine according to the embodiment of
the present invention is shown in Figure-4. This auto levelling 5 system controls
the variation of linear density in sliver and maintains the uniformity consistently
though out the sliver making process. Before the carded sliver (14) is fed into the
drafting unit, a measuring unit (26) senses the variation in cross section of card
sliver. This variation signal is transmitted to electronic control unit (100). This
10 control unit (100) is programmed with a pre-set value or reference value as a feed.
Sliver thickness variance signal compared with said pre-set value by the control
unit (100), which then determines the output of the regulator that provides the
variable speed to the drive for delivering the required draft. Preferably the sliver
thickness is sensed at web calender roller (11) and then the measured value is sent
15 to electronic control unit (100). If control unit finds any difference between the
measured value and pre-set value, then it sends a command to front drafting roller
drive unit (25) to take necessary action for correcting the variation. Said front
drafting roller drive unit (25) comprises at least a variable speed motor.
Additionally or optionally the top roller (17) of front roller may connected to
20 variable speed motor. Corrected variance signal is then measured by measuring
unit (24) using a pair of calender rollers (21) and is transferred back to control
unit (100) and this process continues. Thus the present invention provides better
evenness in terms of uniform sliver thickness only by varying front roller speed of
drafting unit. Meanwhile the remaining rollers like back roller pair of drafting
25 unit, doffer, web doffing and calender roller maintains constant speed to prevent
sliver slackness and possible classimat faults.
In view of the present disclosure which describes the present invention, all
changes, modifications and variations within the meaning and range of
30 equivalency are considered within the scope and spirit of the invention. It is to be
understood that the aspects and embodiment of the disclosure described above may be used in any combination with each other. Several of the aspects and
embodiment may be combined together to form a further embodiment of the
disclosure.
Those skilled in the art will recognize other use cases, 5 improvements, and
modification to the embodiments of the present disclosure. All such
improvements and other use-cases are considered within the scope of the concepts
disclosed herein.
10 Although the disclosure herein has been described with reference to particular
embodiments, it is to be understood that these embodiments are merely illustrative
of the principles and applications of the present disclosure. Many modifications
and variations will be apparent to those skilled in the art. The embodiments have
been selected and described in order to best explain the disclosure and its practical
15 implementations/applications, thereby enabling persons skilled in the art to
understand the disclosure for various embodiments and with the various changes
as are suited to the particular use contemplated. It is therefore to be understood
that numerous modifications may be made to the illustrative embodiments and
that other arrangements may be devised without departing from the spirit and
20 scope of the present disclosure as defined by the appended claims.
The illustrations of overview of the drafting apparatus as described herein are
intended to provide a general understanding of the structure of various
embodiments, and they are not intended to serve as a complete description of all
25 the elements and features of apparatus and systems that might make use of the
structures described herein. Many other arrangements will be apparent to those
skilled in the art upon reviewing the above description. Other arrangements may
be utilized and derived therefrom, such that structural and logical substitutions
and changes may be made without departing from the scope of this disclosure.
30 Figures are also merely representational and may not be drawn to scale. Certain
proportions thereof may be exaggerated, while others may be minimized.
Accordingly, the specification and drawings are to be regarded in an illustrative
rather than a restrictive sense.
Thus, although specific figures have been illustrated and described herein, it
should be appreciated that any other designs calculated to 5 achieve the same
purpose may be substituted for the specific arrangement shown. This disclosure is
intended to cover any and all adaptations or variations of various embodiments of
the present disclosure. Combinations of the above designs/structural modifications
not specifically described herein, will be apparent to those skilled in the art upon
10 reviewing the above description. Therefore, it is intended that the disclosure not
be limited to the particular method flow, device, arrangement and system
disclosed as the best mode contemplated for carrying out this disclosure, but that
the disclosure will include all embodiments and arrangements falling within the
scope of the appended claims.
15
While various embodiments have been described above, it should be understood
that they have been presented by way of example only, and not limitation. Where
methods described above indicate certain events occurring in certain order, the
ordering of certain events may be modified. Additionally, certain of the events
20 may be performed concurrently in a parallel process when possible, as well as
performed sequentially as described above.
WE CLAIM :
5
1. A drafting apparatus for processing textile fibre sliver comprising a drafting
roller unit, a dedicated carrier arm, and a coiler unit with a sliver deposit can;
wherein the drafting roller unit (200) comprises:
a pair of back rollers; said pair of back rollers having a top roller
10 (15) and a bottom roller (16);
a pair of front rollers; said pair of front rollers having a top roller
(17) and a bottom roller (18);
wherein said coiler unit comprise a pair of calender rollers (21) having a
top roller (21b) and a bottom roller (21a), a trumpet guide or sliver funnel
15 (19) and a coiler plate (22);
characterized in that the top rollers (15, 17) of the drafting unit and top
roller (21b) of the calender roller are mounted separately such that the
drafting roller unit (200) and the calender roller unit (21) are
loaded/unloaded irrespective of one another; and wherein the delivery
20 roller pair (17, 18) of said drafting roller unit (200) is provided with
autolevelling system.
2. The apparatus as claimed in claim 1, wherein the top rollers (15, 17) of drafting
25 roller unit (200) are adapted to be opened upward (lifted) and closed (loaded) by
means of the carrier arm (300) which is opened or closed with respect to a hinge
point (400).
30 3. The apparatus as claimed in claim 1, wherein the drafting unit is provided at
40° to 70°, preferably at 60° with respect to coiler plate (22) surface.
4. The apparatus as claimed in claim 1, wherein the auto levelling system is
adapted to control the variation of linear density in sliver and maintains the
uniformity consistently through out the sliver making process.
5
5. The apparatus as claimed in claim 4, wherein the auto levelling system
comprises a measuring unit (26) operably connected with a web calender roller
(11) so as to sense a variation in cross section of card sliver and transmit a
10 variation signal to electronic control unit (100).
6. The apparatus as claimed in claims 4 and 5, wherein said control unit is
configured to compare the received variation signal with a pre-set value and send
15 a command to front drafting roller drive unit (25) comprising at least a variable
speed motor operably connected to the bottom roller (18) of the front roller, to
adjust the speed of the bottom roller (18) of the front roller to correct the
variation, and a measuring unit (24) operably connected with the pair of calender
rollers (21) to sense the corrected variance signal and transmit the same to the
20 control unit (100), thereby providing better evenness in terms of uniform sliver
thickness only by varying front roller speed of drafting unit.
7. The apparatus as claimed in claim 2, wherein the top rollers of drafting unit
25 (200) are mounted in the carrier arm (300) which is opened or closed with respect
to the hinge point (400).
8. The apparatus as claimed in claim 1, wherein the calender rollers pair (21a,
30 21b) and bottom drafting rollers (16, 18) run at slow speed when the top rollers (15 and 17) of the drawing unit (200) are lifted or opened upward during the sliver
piecing operation, and after completion of sliver piecing operation, the top roller
arm (300) is closed or loaded against bottom rollers (16 and 18).
9. The apparatus as claimed in claim 1, wherein a dedicated loading arrangement
(500) is provided for loading / unloading any one of the calender roller pair (21).