WO2023111777A1

WO2023111777A1 - A yarn guiding device for guiding advancing yarn in a turret type autowinder and a method of guiding yarn

Info

Publication number: WO2023111777A1
Application number: PCT/IB2022/061858
Authority: WO
Inventors: Gaurav LOHIA
Original assignee: Lohia Corp Ltd
Current assignee: Lohia Corp Ltd
Priority date: 2021-12-14
Filing date: 2022-12-07
Publication date: 2023-06-22
Anticipated expiration: 2024-06-14

Abstract

The invention discloses a traverse mechanism (6) housed inside a cambox (4) and having a traverse guide (5) and a yam stopper (9) and a method for yam transfer. The traverse guide (5) has a planar body comprising a stem (5k), a right wing (5a) and left wing (5b) having a lip (5e), said wings (5a, 5b) having convex outer edges and concave or straight inner edges, and said lip (5e) shares said outer edge of the left wing as its own outer edge which continues around the lip (5e) to form third inner edge (5h) that enjoins with edge forming the groove (5c). The yarn stopper (9) is affixed to the cambox (4) and has a rigid planar body with an outer end (9b) oriented at a first angle with an inner end (9a) that bends into an inner leg (9c) that is at a second angle with said outer end (9b).

Description

A YARN GUIDING DEVICE FOR GUIDING ADVANCING YARN IN A TURRET TYPE AUTOWINDER AND A METHOD OF GUIDING YARN

Field of Invention

The present invention relates to a yarn guiding device used in yam transfer during yarn winding operation in a turret type autowinder from a full bobbin to an empty bobbin, and method for preventing the yam from coming out of the traverse guide during transfer of continuous advancing yam to the grasping device during the bobbin changeover operation successfully without any failure in winding machine. Further invention also relates to guiding the yarn properly during winding process.

Background of Invention

In the following description, the term "yarn" is intended to also include the threads, tapes, profile tapes, fibrillated tapes and slit-film bands of various linear mass density, diameter, width, and thickness. The term "bobbin" is intended to include any metallic or non-metallic tubes on which the yarn is wound to form a suitable package. The term 'yarn' is also used to describe yam with multiple threads or ends that a single winder might receive. Automatic turret type winders are used in production or take-up process of continuously advancing yarn, for example, in yarn extrusion machines or in rewinding process for making plurality of small size yarn packages from a large yarn package. In general, the turret type automatic winders are positioned side by side in the horizontal direction and stack one above the other in vertical direction. The number of winding positions is exemplary both in horizontal row and vertical row.

The yam transfer operation is important in the automatic yam winding operation. If the yarn is not transferred in the first attempt, the continuously advancing yarn gets wasted until it is rethreaded. Worse still, the continuously advancing yarn, if not controlled properly in case it fails to transfer onto the empty bobbin, may interfere with the other yarn winders on the same machine and cause the entire machinery to stop which results in a huge amount of wastage, machine downtime and economic loss. In the worst situations, some parts of the machinery may get damaged.

In automatic turret type winders, a continuously advancing yam is generally wound on an initially empty bobbin to form a suitable yarn package. When the pre-determined package size (length/diameter/time) is achieved on a bobbin installed on one of the bobbin holders, generally known as a spindle, the continuously advancing yarn is transferred by an automatic transfer device to an empty bobbin installed on another spindle to make a new yam package without interrupting the winding operation. During the bobbin changeover operation, the empty bobbin is positioned in the path of the advancing yarn by rotating the turret. The continuously advancing yarn is then guided onto a yarn grasping device or a catching device by axially shifting or displacing the bobbin spindle or the traversing unit, such that the yam is clamped at grasping device and then laid across the empty bobbin. Simultaneously, the yarn connecting the bobbin under winding and the full bobbin is severed.

Patent DE3106947 (‘6947) discloses a unique traverse guide for handling two yarns. Patent ‘6947 discloses a traversing device of the winding device has a traversing thread guide, for laying at least two flat threads or the like which are wound at least partially overlapped on the winding body, two flat threads which are arranged one behind the other in the direction of travel of the thread and are separated from one another by a guide edge, open thread guide slots are provided. The patent ‘6947 does not addresses the problem of yam coming out of traverse guide, neither it discloses anything about self-picking of the yarn inside the traverse guide. One of the Indian Patent 279181 disclosed a yarn guide and a yarn transfer device and method of transferring yarn into the grasping device. Patent 279181 further discloses various embodiments of yarn guide (5) but does not discloses problem of tape jumping effect and solution during tape transferring at higher speed. According to the patent 279181, the yarn is momentarily stop (for fraction of seconds) so that it can be easily grasp into the grasping device, but it does not disclose the effect of yarn when it is grasped without being stopped.

Another patent US3502282 (‘2282) disclosed a traverse guide which comprises of slotted yarn guide having a yarn guide of wear resistant material for guiding a yam and a flat connecting member rigidly secured to said yam guide; and support of lightweight slidable synthetic material and slidable mounting on at least one fixed guide rail, said support including a plurality of outwardly projecting spaced elastically deformable lugs, said lugs resiliently and elastically receiving and holding said connecting member therebetween in detachable engagement with said support. The patent ‘2282 does not addresses the problem of yarn coming out of traverse guide, neither it discloses anything about self-picking of the yarn inside the traverse guide.

Another patent EP2185454B1 (‘8545) discloses a traverse guide with wings. Patent further addresses the picking of the yam by the grasping device and link require to transfer the yarn from the traverse guide to the grasping device. The patent ‘8545 does not discloses anything about the self-picking of the yam inside the traverse guide at high-speed applications where the tendency of yam coming out of traverse guide is prominent.

Thus, there is a need of a device which can be operated without being slowed down and can prevent yarn from coming out of the yarn guide during bobbin changeover in automated turret type winder. Objects of Invention:

Accordingly, some of the objects of the invention are:

The main object of invention is to provide an apparatus for preventing the yam from coming out of the traverse guide during yarn changeover at all speeds including high speeds.

Another object of invention is to provide a method for preventing the yarn from coming out of the traverse guide during changeover at all speeds including high speeds.

Yet another object of invention is to provide an apparatus for self-picking of the yarn inside the traverse guide particularly during high speed application and bobbin change over.

Yet another objective of this invention to provide an apparatus for smooth transfer of the tape from full to an empty bobbin

Further objective of invention is to increase the transfer rate of the system in continuous line.

Another objective of this invention to provide an apparatus for reducing the manpower involved in handling the machine

Brief Description of Figures:

Figure 1 : A turret type automatic yam winder with yam guiding device

Figure 2: Enlarged plan view of transverse guide

Figure 3 shows a yam stopper and its purpose

Figure 4 shows yam stopper construction

Figure 5 shows yam stopper and traverse guide during yam transfer into yarn reception channel at extreme end List of Parts:

1. Full bobbin

2. Empty bobbin

3. Yam

4. Cam box

5. Traverse guide

5 a. Right wing

5 a'. Outer surface of right wing

5 a”. Inner surface of right wing

5b. Left wing

5b'. Outer surface of left wing

5b". Inner surface of left wing

5c. Groove

5d. Meeting point

5e. Lip

5f. Opening of the groove

5g. Extension of predetermine length

5h. Return profile

5i. Yarn reception channel

5j . Ceramic element

5k. Stem

6. Yam Guiding device

7. Grasping device

8. Spindle

9. Yam stopper

9a. Inner end

9b. Outer end

9c. Inner Leg

10. Axis of traverse guide

11. Axis of the yam stopper Summary of Invention:

The present invention relates to a device for guiding the yarn by preventing the same from coming out of the traverse guide during changeover at high speeds and hence same is a part of a yarn transfer system used for transferring the running yarn from a full bobbin to an empty bobbin ready for winding typically fitted on a winder frame. The invention broadly comprises a yarn guiding device (6) for guiding advancing yarn during yarn winding in a turret type autowinder. More specifically, it comprises a yarn guiding device (6) housed inside a cambox (4) and a yam traverse guide and yarn stopper (9) used in transferring a continuously arriving yam onto an empty bobbin for commencing of winding process during bobbin changeover process in automatic turret winder without any stoppage. This is achieved with the provision of a specially shaped traverse guide, during the bobbin changeover when axial movement of the yarn guiding device take place.

In the present invention, during the bobbin changeover operation, the yam guiding device is moved axially through an actuation device and allows the traverse guide — while maintaining its normal traverse speed at all times — to move beyond the normal yarn winding zone such that the advancing yarn is within the reach of the yarn grasping device of the ready-to-be-wound empty bobbin without letting the yarn jump out of the traverse guide. This is achieved because of the special design of the yam traverse guide.

The jumping phenomena is quite common with conventional yam traverse guide in turret type winders. The advancing yam travels at a speed and in a direction that are different from the speed and direction of travel of the traverse guide. Even as the yarn enters into or grasped by the traverse guide, because of the differences in the speed and directions of travel, the yarn tends to move away from the path of travel of traverse guide causing jumping of the yarn out of the traverse guide. However, tape jumping phenomena is also due to the sudden variation in the winding diameter of bobbin during change over as the tape which is grasped by the grasping device is at a lower diameter as compared to the winding bobbin. Since the grasping device is connected with the spindle so the diameter of the grasping device will be near to the spindle diameter. The cheese tube on which winding happens is overlaid on the spindle such that the diameter to which the yarn is grasped is lower than the diameter to which the yam is wounded over cheese tube. Thus, due to this difference in diameter the yam tends to jump out of traverse guide.

After the yam transfer is completed, the yam guiding device moves back to the normal winding zone. Above said traverse guide helps in reducing the wastage due to unsuccessful changeover by containing the yarn in the traverse guide itself.

Detail Description Of Invention:

A turret type yarn winder is used for winding yam on bobbins to form suitable packages. When a bobbin that is fully wound to its predetermined package size the yarn needs to transfer to an empty bobbin that is ready for winding. As shown in figure 1, the yam guiding device (6) of the present invention essentially comprises a novel traverse guide (5) and a yarn stopper (9), wherein yarn traverse guide (5) travels in direction parallel to the axis of bobbin (as shown by dotted lines) and yam stopper (9) restricts the yam movement of extremes as well as helps in self-picking back into traverse guide (5) in case of yam jump. Further, yarn guide (5) in its yam shift phase during the bobbin changeover, the yarn (3) along with the traverse guide (5) shifts towards the grasping device (7) that is typically provided at the end of spindle (8) on which a bobbin is mounted. When the yam (3) is grasped by the grasping device (7), the traverse guide (5) of present invention ensures that the yarn (3) does not come out of the traverse guide (5) due to tension variation during changeover phase. Once the changeover of bobbin is complete yarn guiding device (6) returns the yam (3) along with the traverse guide (5) to winding position so that the winding of the yam (3) can begin on the empty bobbin (2). The winding position can be anywhere between the position ‘a’ and position ‘b’ such that yarn (3) is wounded on the empty bobbin perfectly. A cambox (4) or a similar traversing arrangement houses the yarn guiding device having traverse guide (5) and yarn stopper (9) of the present invention.

In one of the embodiments, the yarn stopper (9) can be used individually in the winders where the bobbin changeover takes place such that the traverse guide is in stationary condition and yarn is taken out of the traverse guide by some mechanically or pneumatic means.

Figure 2 shows an enlarged view of the traverse guide (5) having a planar body. The traverse guide (5) has a unique shape such that it ensures the yam (3) does not comes out of it during bobbin changeover. The traverse guide (5) has a stem (5k) from which fan out two wings such as right wing (5a) and left wing (5b). Each right and left wing (5a, 5b) has an outer surface and inner surface. The right wing (5a) has outer surface of right wing (5a’) which is preferably convex in shape and inner surface of right wing (5a”) which is preferably concave in shape, similarly the left wing (5b) has outer surface of left wing (5b’) which is preferably convex in shape and inner surface of left wing (5b”) which is preferably concave in shape. The outer surface of the inner as well as outer wing is preferably but not necessarily coated with non-abrasive material such as plasma coating or buffing operation is performed such that it provides a smooth curve for the advancing yarn during bobbin changeover.

Further traverse guide (5) comprises of a groove (5c) which is preferably but not necessarily placed centrally between the wings (5a, 5b). The right wing (5a) and groove (5c) form a meeting point (5d) identified by the area where the curvatures of the outer surface of the right wing (5a’) and that of the groove (5c) sharply depart from each other.

The key aspect of the uniqueness of the traverse guide (5) is that the left wing (5b) has a lip (5e) that is shown in figure 2, which overlaps the opening of the groove (5f) and extends beyond it by a predetermined length (5g). The outer surface of the left wing (5b’) has a return profile (5h) that merges with the groove (5c). In doing so, a yarn reception channel (5i) is formed between the return profile (5h) of the left wing (5b) and the outer surface of the right wing (5a’). the lip (5e) serves as barrier to the yarn (3) which tends to come out of the groove (5c) during bobbin changeover.

Further, the groove (5c) is optionally fitted with a ceramic element (5j) through which the advancing yarn (3) passes. The ceramic element (5j) ensure that least friction is generated and less to no wear and tear of yam (3) happens during winding. During initial thread up when the yarn is wounded on the spindle it is not necessary to pass the yarn through the groove (5c) due to the presence of smooth profile of outer surface of right wing (5b’) and yarn stopper (9) which act as barrier, helps the traverse guide (5) to self-pick the tape into the yam reception channel (5i) inside the groove (5c) for winding as shown in figure 3.

The yarn stopper (9) is a planar rigid body which affix to the Cambox (4) in the same plane as of traverse guide (5). Yarn stopper (9) can be constructed by a wire or a rod, which may be metallic or non-metallic, bend with circular or rectangular cross section to form a special structure such that a curve concave profile is made at the inner end (9a) and a flat profile is made at the outer end (9b). This unique profile of inner end provides the yarn (3) a barrier and further helps yarn (3) to enter in the yam reception channel (5i). The yam stopper (9) can be further constructed from a sheet which can be made from metallic or non-metallic materials and must have enough strength to bear the load of the incoming yarn without bending. The yam stopper (9) can have wear resistance coating made from materials such as ceramic, plasma, titanium, hard chrome, or any other wear resistant coating which can bear the frequent yarn collision with the yam stopper (9).

Figure 4 shows the yarn stopper (9) with angle ‘0’ which can have a range of 20- 40 degrees or more preferably 30 degrees. This angle ‘0’ guides the yam towards the axis of the yarn stopper (9) such that the yarn can easily enter into the yarn reception channel (5i). The yarn stopper having inner end (9a) as a curve profile with an inner leg (9c) which is placed at angle ‘a’ with respect to the outer end (9b). The angle ‘a’ can be taken in the range of 30 - 60 degree or more preferably 45 degree such that the yarn can be guided towards the axis of the yarn stopper (9). The outer end (9a), the inner end (9b) and the inner leg (9c) together form the planar body of the yarn stopper (9).

Figure 5 shows the yam stopper (9) with the traverse guide (5) such that traverse guide (5) reaches to a limit upto which the self-catching of the tape happens. In such condition the axis of traverse guide (10) crosses the axis of the yam stopper (11) resulting in smooth entry of yam into the yarn reception channel (5i).

A yam guiding device (6) is provided, which typically attached to Cambox (4) on winder, guides the yarn (3) towards the grasping device (7) that is provided on the spindle (8). The yarn guiding device (6) can be actuated mechanically , electronically, or pneumatically.

In the present invention, during the bobbin changeover operation, the yarn guiding device (6) is moved axially through an actuation and allows the traverse guide (5) — while maintaining its normal traverse speed — to move beyond the normal yam winding zone or beyond ‘b’ as can be seen from figure 1, such that the yam (3) is within the reach of the grasping device (7) of the ready-to-be- wound empty bobbin (2).

In the yam guiding device (6), the traverse guide (5) will be moved forward and backward during changeover process along with yarn guiding device (6) by any means such as pneumatic or hydraulic pressure, electricity or their combination while maintaining its normal traverse speed.

Some of the prominent advantages of the said traverse guide are:

• 3-5 % increased transfer efficiency in automatic turret type winders. Even such seemingly small increase in efficiency results in significant reduction in waste and labour costs.

• Reduction in wastage of yarn which will lead to cost saving by saving material.

• Eliminating the problem of Tape/Filament coming out of traverse guide, thus reduces the involvement of manpower due to transfer failure during each transfer cycle.

As an example, when a tapeline is running with the melt output of 600kg/hr which is attached to the winder frame having 180 winders heads with the active 180 spindles running at a same time. The speed of the winders is 500 mpm, processing the tape of 1000 denier. Both the conventional traverse guide system and inventive traverse guide are installed on the winders running with the same specifications as indicated above, the annual saving is calculated which is shown below.

Thus, from above chart it is concluded that using the inventive traverse guide annual cost saving of 8,60,160 INR can be achieved.

The method of yarn transfer efficiently from filled bobbin to empty bobbin during change over using inventive yarn guiding device housed in Cambox having traverse guide as well as yarn stopper involves following steps : a) During initial threading, the yarn (3) is wounded on the cheese tube such that it is self-picked by the traverse guide (5) by hitting the unique profile of yarn stopper (9) which acts as a barrier . b) Now the winding starts and after attaining desired diameter the bobbin tends to transfer. c) Such bobbin transfer involves empty bobbin (2) taking the place of the full bobbin (1) due to the rotation of the turret. d) As soon as the empty bobbin (2) takes the place of the full bobbin (1) the yarn guiding device (6) activates and traverse guide (5) moves in the forward direction away from ‘b’ line as shown in figure 1. e) The forward movement of the traverse guide (5) makes the yam to enter into the groove of grasping device (7). f) Due to tension variation, the yarn (3) breaks and yam (3) now tends to wound over the empty bobbin (2). g) Further, during yarn breakage and winding on empty bobbin the yarn tends to come out of the traverse guide (5) from yam reception channel (5i). h) Due to the return profile (5h), the yam (3) again moves back to the groove (5c). i) Now the winding on empty bobbin (2) continues.

It is evident from the foregoing discussion that the invention has a number of embodiments. In its preferred embodiment, the invention discloses a yarn guiding device (6) for guiding advancing yam during yam winding in a turret type autowinder said device comprising a traverse mechanism (6) housed inside a cambox (4) and having a traverse guide (5) and a yam stopper (9). As its characterising feature it discloses that: a. the traverse guide (5) has a planar body comprising a stem (5k) from which fan out a right wing (5a) and left wing (5b) having a lip (5e), each of said wings (5a, 5b) having an outer edge and inner edge, wherein the first outer edge (5a’) of said right wing (5a) is convex in shape and the first inner edge (5a”) of said right wing (5a) is concave or straight in shape, and the left wing (5b) has a second outer edge (5b’) which is convex in shape and the second inner edge (5b”) the left wing (5b) is concave or straight in shape, and wherein said lip (5e) shares said second outer edge as its own outer edge which continues around the lip (5e) to form the third inner edge (5h) that enjoins with the edge forming the groove (5c), and wherein a meeting point (5d) is formed where the edge of the groove (5c) and the first outer edge (5a’) meet, further wherein said lip (5e) protrudes beyond said meeting point (5d) overlapping a portion of said first outer edge(5a’) to form a yam reception channel (5i), and b. said yarn stopper (9) which is affixed to the cambox (4) has a rigid planar body formed by an outer end (9b) that is oriented at a first angle with an inner end (9a) that bends into an inner leg (9c) that is at a second angle with said outer end (9b). In an embodiment of the guiding device (6), the outer edges (5a’ and 5b’) are smoothened by coating them with non-abrasive material such as plasma coating or by buffing operation.

In another embodiment of the yarn guiding device (6), the groove (5c) is placed centrally between said wings (5a, 5b).

In yet another embodiment of the yarn guiding device (6), the groove (5c) is fitted with a ceramic element (5j).

In a further embodiment of the yam guiding device (6), the first angle is in the range of 20-40 degrees, said second angle is in the range of 30 - 60 degrees.

In a still further embodiment of the yam guiding device (6), the first angle is 30 degrees and said second angle is 45 degrees.

In another embodiment of the yarn guiding device (6), the yam stopper (9) is constructed from a sheet made from metallic or non-metallic materials.

In yet another embodiment of the yarn guiding device (6) the yam stopper (9) is constructed from a wire or a rod having a circular or rectangular cross section, said rod or wire being metallic or non-metallic.

In still another embodiment of the yam guiding device (6), the yam stopper (9) has a wear resistance coating made from materials such as ceramic, plasma, titanium, hard chrome, or any other wear resistant coating.

In another preferred embodiment of the invention a method for guiding yam using the yam guiding device (6) is disclosed. The characterised steps of the method are: a. picking up yarn (3) using the traverse guide (5) and starting to wind it on a cheese tube; b. winding said yarn (3) on said cheese tube until the wound tube attains a predetermined diameter and the bobbin is fully wound; c. bringing an empty bobbin in winding position of the turret on which said bobbins are mounted; d. activating said yarn guiding device (6) and moving said traverse guide (5) in forward direction; e. entering the yarn (3) into the groove of a grasping device (7); f. severing the yam (3) from the fully wound bobbin and beginning to wind it on said empty bobbin.

While the above description contains much specificity, these should not be constmed as limitation in the scope of the invention, but rather as an exemplification of the preferred embodiments thereof. It must be realized that modifications and variations are possible based on the disclosure given above without departing from the spirit and scope of the invention. Accordingly, the scope of the invention should be determined not by the embodiments illustrated, but by the appended claims and their legal equivalents.

Claims

Claims:

1. A yam guiding device (6) for guiding advancing yarn during yarn winding in a turret type autowinder said device comprising a traverse mechanism (6) housed inside a cambox (4) and having a traverse guide (5) and a yam stopper (9), characterised in that: said traverse guide (5) has a planar body comprising a stem (5k) from which fan out a right wing (5a) and left wing (5b) having a lip (5e), each of said wings (5a, 5b) having an outer edge and inner edge, wherein the first outer edge (5a’) of said right wing (5a) is convex in shape and the first inner edge (5a”) of said right wing (5a) is concave or straight in shape, and the left wing (5b) has a second outer edge (5b’) which is convex in shape and the second inner edge (5b”) the left wing (5b) is concave or straight in shape, and wherein said lip (5e) shares said second outer edge as its own outer edge which continues around the lip (5e) to form the third inner edge (5h) that enjoins with the edge forming the groove (5c), and wherein a meeting point (5d) is formed where the edge of the groove (5 c) and the first outer edge (5 a’) meet, further wherein said lip (5e) protrudes beyond said meeting point (5d) overlapping a portion of said first outer edge(5a’) to form a yam reception channel (5i); said yarn stopper (9) which is affixed to the cambox (4) has a rigid planar body formed by an outer end (9b) that is oriented at a first angle with an inner end (9a) that bends into an inner leg (9c) that is at a second angle with said outer end (9b).

2. The yarn guiding device (6) as claimed in claim 1, wherein said outer edges (5 a’ and 5b’) are smoothened by coating them with non-abrasive material such as plasma coating or by buffing operation.

3. The yarn guiding device (6) as claimed in claims 1 to 2, wherein said groove (5c) is placed centrally between said wings (5a, 5b). The yarn guiding device (6) as claimed in claims 1 to 3, wherein said groove (5c) is fitted with a ceramic element (5j). The yarn guiding device (6) as claimed in claims 1 to 4, wherein said first angle is in the range of 20-40 degrees, said second angle is in the range of 30 - 60 degrees. The yarn guiding device (6) as claimed in claim 5, wherein said first angle is 30 degrees and said second angle is 45 degrees. The yarn guiding device as claimed in claims 1 to 6, wherein said yam stopper (9) is constructed from a sheet made from metallic or non-metallic materials. The yarn guiding device as claimed in claims 1 to 6, wherein said yam stopper (9) is constructed from a wire or a rod having a circular or rectangular cross section, said rod or wire being metallic or non-metallic. The yarn guiding device as claimed in claims 1 to 8, wherein said yam stopper (9) has a wear resistance coating made from materials such as ceramic, plasma, titanium, hard chrome, or any other wear resistant coating. A method for guiding yarn using the yam guiding device (6) as claimed in claims 1 to 9, characterised in that the method comprises the steps of a. picking up yarn (3) using the traverse guide (5) and starting to wind it on a cheese tube; b. winding said yarn (3) on said cheese tube until the wound tube attains a predetermined diameter and the bobbin is fully wound; c. bringing an empty bobbin in winding position of the turret on which said bobbins are mounted; d. activating said yarn guiding device (6) and moving said traverse guide (5) in forward direction; e. entering the yam (3) into the groove of a grasping device (7); f. severing the yarn (3) from the fully wound bobbin and beginning to wind it on said empty bobbin.