Title of Invention

DEVICE FOR INTERMINGLING A MULTIFILAMENT THREAD

Abstract A device for intermingling a multifilament thread having an elongate thread channel open at both ends is described. The thread channel is formed by a guide region and an expansion region, as seen in cross-section, with an air supply channel opening out into the guide region. For guiding the thread, provided outside the thread channel is a thread guide device which is arranged in a threadline plane with the guide region. In order after major deflection to produce as high-frequency a swing of the thread as possible during the intermingling, the thread channel has a cross-sectional narrowing in the cross-section between the guide region and the expansion region.
Full Text

Device for intermingling a multifilament thread
The invention relates to a device for intermingling a multifilament thread in accordance with the precharacterising clause of Claim 1.
A generic device is known for example from EP 0 976 856 Al.
When synthetic multifilament threads are made, a thread is formed from a plurality of extremely fine filaments in strand form. A thread melt-spun in this way is thus made up of a bundle of a plurality of filament strands. In order to give cohesion to the filament strands for subsequent processing procedures, the multifilament thread is preferably intermingled using compressed air. For this purpose, the thread is guided in a thread channel in which the compressed air is blown through an air supply channel, substantially transversely to the direction of the threadline. During this, the filament strands are interlaced; these interlacings are designated by the term tangle knots. The number of tangle knots per unit length in the thread thus represents an essential measure of the cohesion of the thread.
To produce a knot formation in the thread which is as constant and even as possible, in the case of the known device according to EP 0 976 856 Al the thread channel is formed by a guide region and an expansion region, as seen in cross-section. In this case, the guide region serves to guide the thread, which is deflected out of the guide region into the expansion region by a supply of compressed air. For this purpose, thread guides are associated with the guide region, and these feed the thread into the guide region of the thread

channel and remove it therefrom. In practice, however, it has oeen found that because of the dynamic force inherent in the thread as a result of the intermingling it strikes with great impact in the relatively narrow guide region, which results in a considerable amount of lint being formed in the case of thin filaments, in particular as they enter the thread channel. Moreover, the shaping of the thread channel has the further disadvantage that during the intermingling the thread has a relatively large amount of freedom to swing into the expansion region and the guide region, in particular if the air flow is not sufficiently pressurised. Large swinging movements of this kind result in less frequent knots in the thread, however. A further disadvantage consists in the fact that only a small part of the air flow deflects the filaments, since a large part of the air flows past the closely guided filaments without being of any use.
It is therefore the object of the invention to further develop a device for intermingling a multifilament thread of the generic type such that the above-mentioned disadvantages are avoided and an intensive interlacing with a high frequency of knots is achieved per unit length of the thread.
This object is achieved according to the invention by a device having the features of Claim 1.
Advantageous further developments of the invention are defined by the features and combinations of features in the subclaims.
The invention is based on the realisation that the formation of knots in a thread during intermingling is directly

associated with the amplitude of the swinging movement of the thread in the thread channel. It has thus been found that the smaller the amplitude of swing of the thread in the thread channel, the higher the number of knots produced per unit length in the thread. In order to set the multifilament thread, which during the intermingling is deflected out of the guide region into the expansion region by the air flow, swinging at as small an amplitude as possible, in accordance with the invention the thread channel has a cross-sectional narrowing in the cross-section between the guide region and the swinging region. Thus, the velocity of the air inside the thread channel is increased and additional turbulence is produced which prevents the thread from falling back out of the expansion region into the guide region during intermingling. The thread remains exclusively in a deflected condition inside the expansion region, with the result that the swing stroke is limited during intermingling.
The shape of the intermingling channel is distinguished from known solutions in particular in that it produces high numbers of knots even at relatively low air pressures.
To give the thread sufficient freedom in the guide region, the width of the guide region is made larger in the cross-section of the thread channel than the width of the cross-sectional narrowing. This reduces impact against the walls of the thread channel in the guide region even with relatively large dynamic thread movements.
In a particularly advantageous further development of the invention in which the air supply channel has an entry cross-section with an opening width which is greater than or equal

to the width of the cross-sectional narrowing, the result is that the thread remains securely deflected inside the expansion region by the supplied air flow and so performs a swing of small amplitude. In particular in those cases in which the opening width of the air supply channel is greater than the width of the cross-sectional narrowing, an effect of accelerating the air flow occurs within the thread channel. This effect means that on the one hand all the filament strands are taken hold of at a high level of intensity and on the other any backflow of the air out of the expansion region into the guide region is completely eliminated.
The preferred further development of the invention in which the channel wall of the thread channel has a guide contour, for diverting the air flow which occurs, in the expansion region opposite the air supply channel is distinguished by the fact that controlled guidance of the air allows the smooth movement of the thread or the swing behaviour of the thread or additional effects to be generated as the thread is intermingled.
Thus, the further development of the invention in which the guide contour is formed by a convex curvature aligned centrally with respect to the air channel has proved particularly useful. This produces a symmetrical division and diversion of the air flow striking against the wall, which has the effect of holding the thread substantially centrally in the expansion region. This makes the movement of the thread smoother, which is particularly advantageous in the upstream and downstream treatment stages.

Thus, for example, the overall cross-section of the thread channel may be in the form of three at least partly overlapping portions of circular cross-section, with the centre points of the portions of circular cross-section being arranged in a triangle with its apex facing the air channel. The expansion region of the thread channel can thus be made in a simple way from two overlapping bores and the guide channel may be made from a further bore, with the cross-sectional narrowing in the form of a nozzle which has correspondingly rounded edges.
The guide contour may, however, also be in the form of a concave curvature which is aligned asymmetrically with respect to the air channel. This has the effect of guiding the air flow, which in addition to the interlacing of the filament strands performs a twist action on the filament bundle. This improves the cohesion of the thread.
As well as the geometric form of the thread channel, the thread guide also has an influence on improving the characteristics of the intermingling. The guide device associated with the thread channel may thus be formed by two thread guides which are arranged upstream or downstream of the thread channel along the threadline and which may preferably be positioned in the direction of the threadline. This construction has the advantage that the intermingling of the thread may be performed at any point along the threadline.
i In practice, however, guide devices by means of which a high degree of integration of the intermingling in the procedures for treatment of the thread is achieved have proved useful.

For example, the guide device may advantageously also be formed by a deflection pin and a godet which are arranged upstream and downstream of the thread channel along the threadline, with the thread being deflected at the deflection pin transversely with respect to the longitudinal direction of the thread channel, preferably before it runs through the thread channel. This arrangement has the advantage that, as a result of the deflection point at the deflection pin, the thread always enters the thread channel in the same position. Even dynamic movements in the thread do not bring about any changes.
In order to ensure that the thread comes into the guide region as it is threaded into the thread channel, the further development of the invention in which the insertion slot and the air supply channel are connected, in a common opening-out plane, to the guide region of the thread channel is particularly advantageous. This means that the compressed air supplied by way of the air supply channel acts in the same direction as the threading-in movement, with the result that even if there is a thread in the insertion slot it is blown into the guide region of the thread channel at the start of the intermingling, by the compressed air.
When melt-spun threads are being made, conventionally a plurality of threads, for example twelve or sixteen threads, are produced in parallel next to one another. For the intermingling, in this case each of the threads has to be guided through a thread channel individually. The further development of the invention in which a plurality of thread channels of identical construction are arranged next to one another, with an air supply channel and an insertion slot

being associated with each thread channel and with two adjacent insertion slots of two adjacent thread channels opening out into a common collecting insertion slot, has proved particularly useful- This makes it possible to intermingle all the threads in regions in which the threads are guided with the minimum of clearance from one another of, for example, Some example embodiments of the device according to the invention are described in more detail below with reference to the attached drawings, in which:
Fig. 1 illustrates diagrammatically a longitudinal section through a first example embodiment of the device according to the invention
Fig. 2 illustrates diagrammatically a cross-section through the example embodiment of Fig. 1
Fig. 3 illustrates diagrammatically a cross-section through a further example embodiment of the device according to the invention
Fig. 4 illustrates diagrammatically a cross-section through a further example embodiment of the device according to the invention
Fig. 5 illustrates diagrammatically a view of a further example embodiment of the device according to the invention

Fig. 6 illustrates diagraininatically a cross-section through a further example embodiment of the device according to the invention
In Figs. 1 and 2, a first example embodiment of the device according to the invention is illustrated diagrammatically. Fig. 1 shows a longitudinal section and Fig. 2 shows a cross-section of the device. The description below applies to both figures unless express reference is made to one of the figures.
The example embodiment has, in a base body 15, an elongate thread channel 1 open at both ends. The base body 15 is cuboid in form. The thread channel 1 has a two-part cross-section composed of a guide region 4 and an expansion region 2. The guide region 4 and the expansion region 2 are connected to one another by way of a cross-sectional narrowing 3.
Outside the thread channel 1 there is arranged a guide device for guiding through the thread guides 7.1 and 7.2. The thread guide 7.1 in the threadline upstream of the thread channel 1 and the thread guide 7.2 in the threadline downstream of the thread channel 1 are arranged in a common threadline plane with the guide region 4. The thread guides 7.1 and 7.2 may preferably be positioned in the direction of the threadline, with the result that the free length of thread between the thread guides 7.1 and 7.2 is variable.
An air supply channel 5 opens out into the guide region 4 of the thread channel 1 and is aligned transversely with respect to the longitudinal axis of the thread channel 1. The air

supply channel 5 is attached by way of a compressed air line to a pressurised source (not illustrated here).
For threading-in of the thread, the guide region 4 of the thread channel 1 is connected to an insertion slot 6 over its entire length. The insertion slot 6 and the air supply channel 5 are for this purpose arranged in a common opening-out plane in order to open out into the guide region 4 in the same direction. The insertion slot 6 is formed in an L shape and ends at the side of the base body 15.
Fig. 2 illustrates the cross-section through the thread channel 1 on a larger scale. Here, the supply of air from the air supply channel 5 is drawn in as a dotted line on the underside of the base body 15. The expansion region 2 of the thread channel 1 has a guide contour 9 on the channel wall opposite the air supply channel 5. The guide contour 9 is formed by a convex curvature 10 aligned centrally with the air supply channel. The air supply channel 5 has an entry cross-section having an opening width L. The opening width L of the air supply channel 5 is the same size as the width E of the cross-sectional narrowing 3. The cross-sectional narrowing 3 having the width E provides the connection between the guide region 4 and the expansion region 2. In this context, the guide region 4 has a width F and the expansion region 2 has the width S. The overall cross-section of the thread channel 1 is in this case constructed to be symmetrical with respect to the centre axis of the air supply channel 5. The width F of the guide region is larger than the width E of the cross-sectional narrowing 3, with the width F of the guide region 4 being dimensioned such that thread guidance is as free of contact as possible. By contrast, the

tfidth S of the expansion region 2 is constructed to be substantially larger than the width F of the guide region 4.
In order to intermingle a multifilament thread 8 formed by a plurality of filament strands, the thread 8 is first of all guided by way of the thread guides 7.1 and 7.2 through the guide region 4 of the thread channel 1. For this purpose, the thread 8 is threaded into the guide region 4 by way of the insertion slot 6. For intermingling, a flow of compressed air is first introduced into the guide region 4 by way of the air supply channel 5. The flow of compressed air, designated in Fig. 2 by arrows, takes hold of the thread 8 and guides it into the expansion region 2. The threadline is illustrated in Fig. 1, with the threadline shown in dotted lines in the guide region 4.
In the expansion region 2, the air flow strikes against the guide contour 9 and is diverted thereby such that substantially two partial flows are produced distributed evenly in the expansion region. At the same time, the cross-sectional narrowing 3 ensures that there is no backflow into the guide region 4. Thus, the thread 8 remains in the expansion region 2. The clearance between the cross-sectional narrowing 3 and the guide contour 9 of the expansion region 2, designated by capital letter H in Fig. 2, represents a measure of the maximum amplitude at which the thread 8 swings. The way the thread channel 1 is shaped in accordance with the invention makes it possible to limit the amplitude so that particularly high-frequency swings can be produced in the thread 8, resulting in a large number of tangle knots per unit length of the thread. In comparative tests, by comparison with the device known from the prior art an

Improvement of approx. 30% was achieved in the frequency of the knots per unit length.
The capacity of the thread to swing during the intermingling is also substantially determined by the deflection of the thread from the guide region 4 into the expansion region 2. Positioning the thread guides 7.1 and 7.2 allows the deflection and the tension states associated therewith to be influenced, so that additional measures to increase the capacity to swing can be taken.
Fig. 3 shows diagrammatically a cross-section through a further example embodiment of the device according to the invention. The structure of the device is substantially identical to that of the previous example embodiment, so that only the differences will be pointed out here.
The thread channel 1 formed by the expansion region 2 and the guide region 4 has an overall cross-section which is asymmetrical with respect to the centre axis of the air supply channel 5. For this purpose, the guide contour 9 in the expansion region 2 is formed by an eccentrically convex curvature 11. The expansion region 2 as a whole therefore has a partial cross-section which lies asymmetrically with respect to the cross-sectional narrowing 3 and the guide region 2. As a result of this asymmetry of the thread channel 1, the air flow is influenced such that an air flow entering the expansion region 2 is preferably deflected to one side. In this context, once again the cross-sectional narrowing 3 has the effect of substantially preventing backflow, so that an air flow which is directed to one side is established in the expansion region 2. This air flow has the effect of

twisting the filament bundle in a manner overlaid on the intermingling.
An additional effect is achieved with the embodiment illustrated in Fig. 3, namely that the opening width L of the air supply channel is the same size as the width F of the guide region. The guide region 4, which has two mutually inclined flanks opening out into the cross-sectional narrowing 3, makes it possible for the air flow entering the expansion region to be directed. The air flow flowing out of the guide region 4 by way of the cross-sectional narrowing 3 into the expansion region 2 is thus accelerated within the thread channel. Additionally, backflow of the air into the guide region is suppressed.
Fig. 4 shows a further example embodiment of an overall cross-section of a thread channel 1. The overall cross-section of the thread channel 1 is in this case formed by three at least partly overlapping portions of circular cross-section, with the centre points of the portions of circular cross-section being arranged in a triangle with its apex facing the air supply channel 5. A clover-shaped hollow in the overall cross-section of the thread channel 1 is thus produced. The expansion region 2 is formed by two overlapping portions of circular cross-section whereof the centre points lie in a plane perpendicular to the centre axis of the air supply channel 5. The portions of circular cross-section have radii of the same size, designated by lower-case letter r. The guide region 4 is formed by a further portion of circular cross-section which is arranged centrally with respect to the portions of circular cross-section of the expansion region 2. The portion of circular cross-section of the guide region 2

may be formed with a radius r of the same size or larger. The cross-sectional narrowing 3 formed between the overlapping portions of circular cross-section is formed by roundings. An overall cross-section of this kind for the thread channel can be made simply by multiple bores in the base body 15.
Fig. 5 shows an arrangement of the device according to the invention which makes it possible to integrate it into the treatment procedures of synthetic threads to a high degree. Here, the guide device is formed by a godet 12 and a deflection pin 13 which are arranged upstream and downstream of the thread channel. The base body 15 with the thread channel 1 is in this case arranged directly in the threadline of the thread 8 running onto the godet 12. Before it runs through the thread channel 1, the thread is deflected out of a direction of the threadline onto the longitudinal axis of the thread channel 1 at the deflection pin 13. The deflection pin 13 is for this purpose formed in an L shape, with the thread guided in the groove in the deflection pin 13. The groove in the deflection pin 13 is aligned centrally with respect to the guide region of the thread channel 1. As a result of this guidance of the thread and construction of the thread guide, the thread is given a high capacity to swing. Both as the thread enters and as it exits, no substantial tension states occur to prevent the thread from performing the deflection movement during intermingling. Moreover, the thread 8 is prevented from impact on entering the thread channel 1.
In order, when making a plurality of threads in one spinning procedure, to intermingle the threads in a common device, an example embodiment is illustrated in Fig. 6 in which a

plurality of thread channels are arranged next to one another in a base body 15. The thread channels 1 may here correspond to the construction in the example embodiments mentioned above. Associated with each of the thread channels 1 are an insertion slot 6 and an air supply channel 5. The air supply channels 5 of the thread channels 1 are preferably supplied by way of a common compressed air line 16. For the threading-in of the threads, a collecting insertion slot 14 is arranged between each two adjacent thread channels 1. The collecting insertion slot 14 is connected at a closed end to in each case two insertion slots 6, which are each associated with one of the adjacent thread channels 1. This makes a compact construction possible.



Claims
1. A device for intermingling a multifilament thread having
an elongate thread channel (1) open at both ends and formed
by a guide region (4) and an expansion region (2), as seen in
cross-section, with the guide region (4) having a smaller
width than the expansion region (2) and with an air supply
channel (5) opening out into the guide region (2), having
outside the thread channel (1) a thread guide device (7.1,
7.2) which lies in a threadline plane with the guide region
(4) of the thread channel (1), and having an elongate
insertion slot (6) connected to the guide region (4) of the
thread channel (1), for threading the thread into the thread
channel {1),
characterised in that
the thread channel (1) has a cross-sectional narrowing (3) in the cross-section between the guide region (4) and the expansion region (2).
2. A device according to Claim 1, characterised in that the cross-sectional narrowing (3) has a width (E) smaller than the width (F) of the guide region (4).
3. A device according to Claim 1 or 2, characterised in that the air supply channel (5) has an entry cross-section having an opening width (L) which is greater than or equal to the width (E) of the cross-sectional narrowing (3).
4. A device according to one of the preceding claims, characterised in that the channel wall of the thread channel (1) has a guide contour, for diverting the air flow which

occurs, in the expansion region (2) opposite the air supply channel (5).
5. A device according to Claim 4, characterised in that the guide contour (9) is formed by a convex curvature (10) aligned centrally with respect to the air channel (5).
6. A device according to Claim 5, characterised in that the overall cross-section of the thread channel (1) is in the form of three at least partly overlapping portions of circular cross-section, with the centre points of the portions of circular cross-section being arranged in a triangle with its apex facing the air supply channel (5) .
7. A device according to Claim 4, characterised in that the guide contour (9) is formed by a concave curvature (11) which is aligned asymmetrically with respect to the air supply channel (5) .
8. A device according to one of the preceding claims, characterised in that the guide device is formed by two thread guides (7.1, 7.2) which are arranged upstream and downstream of the thread channel (1) along the threadline and which may preferably be positioned in the direction of the threadline.
9. A device according to one of Claims 1 to 7, characterised in that the guide device is formed by a godet (12) and a deflection pin (13) which are arranged upstream and downstream of the thread channel along the threadline, with the thread being deflected before or after it runs through the thread channel (1).

10. A device according to one of the preceding claims, characterised in that the insertion slot (6) and the air supply channel (5) are connected, in a common opening-out plane, to the guide region (4) of the thread channel (1).
11. A device according to one of Claims 1 to 10, characterised in that a plurality of thread channels (1) of identical construction are arranged next to one another in order to intermingle a plurality of threads in parallel next to one another, with an air supply channel (5) and an insertion slot (6) being associated with each thread channel and with two adjacent insertion slots (6) of two adjacent thread channels (1) opening out into a common collecting insertion slot (14).

12. A device for intermingling a multifilament thread substantially as herein described with reference tc the accompanying drawings.


Documents:

114-CHE-2004 AMENDED CLAIMS 05-12-2011.pdf

114-CHE-2004 AMENDED PAGES OF SPECIFICATION 05-12-2011.pdf

114-CHE-2004 POWER OF ATTORNEY 05-12-2011.pdf

114-CHE-2004 EXAMINATION REPORT REPLY RECEIVED 05-12-2011.pdf

114-che-2004-abstract.pdf

114-che-2004-claims.pdf

114-che-2004-correspondnece-others.pdf

114-che-2004-description(complete).pdf

114-che-2004-drawings.pdf

114-che-2004-form 1.pdf

114-che-2004-form 26.pdf

114-che-2004-form 3.pdf

114-che-2004-form 5.pdf

114-che-2004-other documents.pdf


Patent Number 250537
Indian Patent Application Number 114/CHE/2004
PG Journal Number 02/2012
Publication Date 13-Jan-2012
Grant Date 09-Jan-2012
Date of Filing 16-Feb-2004
Name of Patentee SAURER GmbH & Co. KG
Applicant Address LANDGRAFENSTRASSE 45 D-41069 MONCHENGLADBACH
Inventors:
# Inventor's Name Inventor's Address
1 WEIGEND HELMUT AUF DER BREDE 79C D-42477 RADEVORMWALD
2 SCHULZ, DETLEV HOHWEG 16 D-42477 RADEVORMWALD
PCT International Classification Number D02J1/08
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 103 06 657.8 2003-02-18 Germany