| Title of Invention | A METHOD FOR OPERATING A SPINNING DEVICE |
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| Abstract | A method for operating a spinning device comprising a centrifugal spinning element rotating at high speed and also a thread guide tube dipping into the centrifugal spinning element having a re-reeling tube displacebly disposed on the thread guide tube, whereby the thread guide tube performs, relative to the centrifugal spinning element, a traversing travel and a superimposed advancing movement downwards and in so doing deposits a yarn package with a cop winding on the inner wall of the centrifugal spinning element characterized in that before introducing the rewinding process, the thread guiding tube (7) is brought by a drive (8) to a rewinding position (31) that is respectively dependant on the last lower dead point of the traverse stroke of the thread guiding tube (7), whereby the last traverse stroke of the thread guider (7) always runs upwards in the direction of the rewinding position (31), after the thread guiding tube (7) is lower by a defined stretch; the stinking rewinding sleeve (9) introduces the rewinding process; and after completion of the rewinding process the thread guiding tube (7) is driven to pre-determined lower position and thereby the spinning cop (36) generated by the rewinding process is shifted to a defined doff position. |
| Full Text | The invention relates to a method for operating a spinning device in accordance with the dosclosure heneunder In the case of centrifugal spinning a feed material, for example a sliver stored in a sliver can or a roving disposed on a speed frame bobbin, is firstly drawn by means of a drafting arrangement to a desired yarn fineness and then is conveyed via an axially displaceably mounted thread guide tube into a spinning centrifuge rotating at high speed. The drawn feed material emerging from the mouth of the thread guide tube is at the same time laid against the inner wall of the spinning centrifuge, with the formation of a yarn thread, and is entrained by it. This means that the fibre material obtains a rotation by the rotation of the spinning centrifuge, so that a thread is formed. The thread produced by the rotation is deposited by the axially displaceably mounted thread guide tube on the inner wall of the centrifuge and forms a yarn package there, which is also called a spinning cake. In the case of the so-called single-step spinning, the centrifugal speed and the delivery speed of the feed material are matched to one another so that the thread deposited as spinning cake already has its complete rotation and in a following operating cycle can be preferably rewound onto a re-reeling sleeve kept ready on the thread guide tube. The spinning cop produced during this re-reeling operation is then doffed and subsequently re-reeled on a bobbin winding machine following in the production sequence with further spinning cops to form a large-volume cross-wound bobbin. The known centrifugal spinning devices may in this case significantly differ, for example with respect to the shape of their spinning centrifuges. From DE 198 02 656 Al, for example, is known a centrifugal spinning device which comprises a tubular spinning centrifuge, i.e. it is open at the top and bottom. From above a thread guide tube, on which a re-reeling sleeve is displaceably kept ready, engages from above into the spinning centrifuge. The centrifugal spinning element is supported via a permanent magnet bearing and is supplied by an electromagnetic drive. With such tubular spinning centrifuges the electromagnetic drive is as a rule disposed between the bearings. Furthermore, centrifugal spinning devices having a so called pot centrifuge are known from DE 42 06 031 C2, DE 44 26 897 Al or DE 42 36 37 6 Al, for example. With these known centrifugal spinning devices, the thread guide tube is passed through the centrifuge neck and, as customary, can be traversed and simultaneously be axially displaced in the direction of a lower centrifuge opening. With such centrifugal spinning devices the re-reeling sleeve is introduced through the centrifuge opening placed at the bottom into the spinning centrifuge. Since such pot centrifuges are only accessible from underneath, it has to be ensured that the spinning cake deposited on the inner wall of the spinning centrifuge is accessible or remains doffable at any time, i.e. after a thread breakage during spinning and also after a lap breakage during re-reeling. As can be seen, for example, from the drawings of DE 42 36 376 Al or DE 44 26 897 Al, in such pot spinning devices work is generally carried out with speed frame winding. In other words, the spinning cake deposited by means of the thread guide tube on the inner wall of the pot centrifuge comprises a winding in the manner of a speed frame bobbin. Such a speed frame winding has the advantage, on account of its structure, that it remains accessible after a thread breakage during the spinning process or after a lap breakage during the re-reeling operation. The produced spinning cops often give rise to difficulties during subsequent operating processes since the postconnected cross-wound bobbins are as a rule designed for using ring spinning cops. Proceeding from the above-mentioned prior art, the object of the invention is to develop a method for operating a centrifugal spinning device which ensures that a yarn package can be produced in the event of a thread breakage during the spinning process and also in the event of a lap breakage during the re-reeling process and can be doffed, which can subsequently be further processed by automatic cheese winders. This object is achieved in accordance with the invention by a method as described later. The method according to the invention has the particular advantage that it reliably prevents a yarn chord being accidentally caught and as a result a re- reeling operation being initiated in an uncontrolled manner, in particular after a thread breakage during the spinning process, since a re-reeling operation initiated in an uncontrolled manner results at least in an unusable spinning cop, and often even in damage to the centrifugal spinning machine. Moreover, the yarn package rewound onto the re-reeling sleeve always has a predetermined position on the re-reeling sleeve, irrespective of the time when the re-reeling operation was initiated, which is extremely advantageous, in particular with respect to the subsequent further processing of the spinning cops in the preparatory stations of the automatic cheese winders. In an advantageous embodiment of the invention it is also provided, that the re-reeling sleeve is lowered to initiate a re-reeling operation at a feed speed which is matched to the vertical unwinding speed of the thread deposited as yarn cake. This means that the feed of there re-reeling sleeve is greater than the vertical unwinding speed of the thread. In this manner it is ensured that the yarn cake can be completely rewound on the re-reeling sleeve and in a later operation can be unwound again. The vertical unwinding speed of the thread can be influenced in different ways via the trasversing motion of the thread guide tube. In a preferred embodiment described herein, it is provided, for example, that the introduction of the thread guide tube into the re-reeling position takes place at a traversing speed which is significantly lower than the traversing speed of the thread guide tube during the regular spinning process. In connection with a corresponding fast feed of the re-reeling sleeve, it is in this manner guaranteed that the yarn package is properly re-reeled from the beginning onto the re- reeling sleeve with a predetermined yarn volume is reached, i.e. at the end of a regular spinning process. Alternative possibilities of influencing the vertical unreeling speed of the thread by the appropriate displacement of the thread guide tube into the re-reeling position are described respectively. It is also provided, for example, that the thread guide tube is displaced at "normal" traversing speed into the re-reeling position and then stays in this position for a while. This means that the feed of there-reeling tube is initiated with a time delay. A time-delayed initiation of the feed of the re-reeling sleeve is also provided in the embodiment described herein. Here too the thread guide tube is firstly displaced at "normal" traversing speed into the re-reeling position, but then in this region performs a few short traversing travels have a positive effect on the deposition of the thread, i.e. the deposited thread layers can be unwound very easily. In an advantageous embodiment it I also provided that, when introduced into the re-reeling position, the re-reeling sleeve is displaced by a distance which, comprises the height of the winding cone of the yarn package, the setback of the re-reeling sleeve and also the length of the unwound end of the re-reelling sleeve. The distance by which the re-reeling sleeve is displaced to initiate the re-reeling operation is advantageously roughly 50 mm. As already stated above, this 50 mm is produced from the so-called setback of the re-reeling sleeve, the height of the winding cone of the yarn package and also the length of the free, unwound sleeve end. In other words, with a sleeve feed of roughly 50 mm a sufficient safety distance of the fixed re-reeling sleeve can be achieved in relation to the rotating yarn thread and also it is guaranteed by the free sleeve end that the spinning cop remains easy to operate in subsequent operations. The spinning cops designed in such a manner can be operated by inner grippers and also by outer grippers. minus twice a end safety distance of for example 5 mm respectively. In this case the safety distances primarily guarantee a safe deposition of the yarn cake on the inner wall of the centrifugal spinning element. The minimum length of the re-reeling sleeve is correspondingly calculated from the maximum length of the yarn package plus the length of the two free, unwound sleeve ends. To prevent, upon the occurrence of a thread breakage, the thread guide tube or the re-reeling sleeve being able to detect a thread chord and at the same time being able to initiate a re-reeling operation in an uncontrolled manner, it is also provided, that the traversing speed of the thread guide tube is matched to the reaction time of the sensor detecting a thread breakage. This means that the reaction time of the sensor has to be dimensioned so that it is ensured that in the event of a thread breakage the thread guide tube performs a traversing motion in the direction of the re-reeling position before the lower end of the re-reeling sleeve reaches the region of the thread breakage. Further details can be gathered from the exemplified embodiments explained below with reference to the/drawings. Therein: Figure l shows, in side view, a centrifugal spinning machine as used to perform the method according to the invention, Figures 2A to 2E shows the individual method steps when rewinding a yarn package at the end of a regular spinning process, Figures 3A to 3E show the individual method steps when rewinding a yarn package after a thread breakage that occurred during the spinning process, Figures 4A to 4C show various refinements of the sequence of the displacement of the thread guide tube into the re-reeling position by using a path-time diagram. Figure 1 diagrammatically shows a first embodiment of a centrifugal spinning device 1, as may avantageously be used to perform the method according to the invention. The centrifugal spinning device 1 comprises a centrifugal spinning element 3 in the form of a so-called pot centrifuge. The centrifugal spinning element 3 rotating in a spinning housing 2 is supported in bearings 4 and is driven by a single motor via an electromagnetic drive 5. In the shown embodiment, the bearings 5 are constructed as magnet bearings, preferably as permanent magnet bearings. As can be seen from Figure 1, the neck region of the pot centrifuge is penetrated by a traversing and simultaneously axially downwardly displaceable thread guide tube 7. For this purpose, the thread guide tube 7 that can be introduced into the centrifugal spinning element is connected to a drive 8 that is only diagrammatically indicated in the figures. The thread guide tube 7 performs a traversing travel 30, i.e. the thread guide tube 7 is traversed respectively between the upper and lower dead centres 24A and 24B respectively and in so doing is axially displaced. Displaceably mounted on the thread guide tube 7 is a re-reeling sleeve 9, which, for example, is connected to the hollow piston rod of a pneumatic cylinder 10 that surrounds the thread guide tube 7 and can be controlled in a defined manner. The re-reeling sleeve 9 is fixed via the pneumatic cylinder with respect to the thread guide tube 7 in a position of rest 33 during the normal spinning process and can be moved into a re-reeling position 34 to initiate the rewinding operation, as will be explained in further detail below. Instead of the pot centrifuge, the centrifugal spinning device 1 can also comprise a tubular spinning centrifuge, as shown, for example, in Figures 2A, 2B and 3A, 3B. Such an embodiment also comprises a thread guide tube 7, which engages from above into the tubular spinning centrifuge 3. Displaceably disposed on the thread guide tube is, as known, a re-reeling sleeve 9. The re-reeling sleeve 9 is positioned in its position of rest 33 on the thread guide tube 7 so that the lower edge 11 of the re- reeling sleeve 9 is slightly set back in relation to the mouth 12 of the thread guide tube 7. This distance, denoted below as the sleeve setback 21, is preferably roughly 5 nun. Both embodiments of a centrifugal spinning device 1 also have a sensor device 13 or 13A for detecting a thread breakage and also a thread release device 14 for initiating an external rewinding operation. The sensor device 13 or 13A is respectively connected to a control unit 19 belonging to the spinning station via a signal line 20 or 20A respectively. Depending on the embodiment, the sensor device 13 is either disposed beneath the drafting arrangement 6 and then monitors the moving feed material 18 or the sensor device 13A is positioned, as indicated by broken lines, beneath the centrifugal spinning element and then monitors the rotation of the rotating yarn thread 28. In such a case the sensor device 13A is constructed as a photoelectric sensor, for example. Furthermore, a thread release device 14 is provided for the external initiation of a rewinding operation. The thread release device 14 is used, for example, after a thread breakage during the spinning process or after a lap breakage during the re-reeling operation and has a drive 23, which enables a displacement of the thread release element 14 parallel to the inner wall 25 of the centrifuge. The thread release element 14 has a cutting edge 16 that can be placed at the winding cone 22 of the yarn package 15 and also a thread guide contour 17 gripping over the cutting edge 16 in the axial direction. A sliver drafting device, for example a drafting arrangement 6, is respectively disposed above the centrifugal spinning element 3. A sliver is either supplied to this drafting arrangement 6 from a sliver can (not shown) or a feed material is supplied to said drafting arrangement 6 from a speed frame bobbin (not shown either). The correspondingly drafted feed material 18 is at the same time conveyed into the interior of the centrifugal spinning element 3, where it, with the formation of a rotating yarn thread 28, is applied to the inner wall 25 of the rotating centrifugal spinning element 3 and in so doing obtains a rotation. The thread produced by the rotation is positioned by the thread guide tube 7 on the inner wall 25 of the centrifugal spinning element 3 so that a defined yarn package, a so- called spinning cake 15, is produced. During the establishment of the yarn package 15, which begins in the region of the bottom 26 of the centrifugal spinning element 3, the thread guide tube 7 is moved up and down in oscillating fashion via the drive 8. At the same time the thread guide tube 7 is continuously lowered in the direction of the centrifuge opening 17 via the drive 8. The spun thread is as a result deposited on the inner wall 25 of the centrifugal spinning element 3 in the manner of a so-called cop winding. If the yarn package 15 has reached a predetermined size or if a thread breakage occurs during the spinning process, a re-reeling process is initiated in accordance with the invention by the following methods: With a regular spinning end, the method indicated in Figures 2A TO 2E takes place, whereas in the event of a thread breakage during the spinning process the method shown in Figures 3A to 3E is used. With a regular spinning end, the last yarn layer of the yarn package 15 is always laid by the thread guide tube 7 being displaced from the position indicated in Figure 2A in the region of the lower edge 29 of the winding cone 22 of the yarn package 15, which is identical with the last bottom dead centre 24A of the traversing travel 30, to the upper dead centre 24B of the traversing travel 30. This last upward traversing motion 32 of the thread guide tube 7 indicated in Figure 4A by means of a path-time diagram preferably has a significantly lower traversing speed than the traversing speed of the thread guide tube 7 customary during the "normal" spinning process. As soon as the thread guide tube 7 has reached the upper dead centre 24B, which in this case is identical with the re-reeling position 31, the re-reeling process is started. In other words, the re-reeling sleeve 9 fixed on the thread guide tube 7 in a position of rest 33 is pushed into its re- reeling position 34 by appropriate control of the pneumatic cylinder 10. During the relatively fast sleeve feed, the lower edge 11 of the re-reeling sleeve 9 firstly brushes over the region of the sleeve setback 21, then is pushed beyond the mouth 12 of the thread guide tube 7 and reaches the region of the lower, free sleeve end 35 of the re- reeling sleeve 9, after the height of the winding cone 22 of the yarn package 15 has been passed. During this action the re-reeling sleeve 9 catches by its lower edge 11 the rotating yarn thread 28, which triggers the re-reeling process. In other words, the spinning cake 15 deposited on the inner wall 25 of the centrifugal spinning element 3 with an upper (39) and a lower (39A) safety distance is rewound onto the re-reeling sleeve 9, as indicated in Figures 2C and 2D, with the winding operation always taking place in the region of the upwardly moving winding cone 22. As the first winding layer is firstly unwound towards the free sleeve end 35, the feed speed of the re-reeling sleeve 9 has to be greater in the region of the winding cone 22 than the axial unwinding speed of the thread. After the yarn package 15 has been completely re-wound onto the re-reeling sleeve 9 and as a result a spinning cop 36 has been produced, the spinning cop 36 is moved by axial displacement of the thread guide tube 7 to a stop 37, which defines the doffing position of the spinning cop 36, as shown in Figure 2E. The spinning cop 36 can then be conveyed further by means of a transport device 38, only diagrammatically indicated in Figure 3E, to a textile machine (not shown) that is postconnected in the production process, preferably a bobbin winding machine. The method according to the invention proceeds in a similar manner when a thread breakage occurs during the spinning process, which is indicated in Figures 3A - 3E. Such a thread breakage is detected immediately by the sensor device 13 and is reported to the control unit 19 via the signal line 20. The control unit 19 then ensures that firstly the further supply of feed material 18 is stopped and secondly the drive 8 of the thread guide tube 7 is controlled in such a manner that the thread guide tube 7 passes immediately into an upward traversing motion 32 or, if at the time of the thread breakage an upward traversing motion exists, this is retained. As soon as the thread guide tube 7 then has reached the re-reeling position 31, in this case too the traversing of the thread guide tube 7, for example, is also ended. To prevent a chord caused by the thread breakage being caught in uncontrolled manner by the thread guide tube 7 or the re-reeling sleeve 8 and thus a damaging re-reeling operation being able to be started, the downward traversing speed of the thread guide tube 7 and also the sleeve setback 21 are matched to the reaction time of the sensor device 13 or 13A respectively. This means that it is ensured that the lower end of the re- reeling sleeve 9 does not get lowered to the level of the thread breakage by the traversing. Then the re-reeling sleeve 9 is pushed into its re-reeling position by means of the pneumatic cylinder 10 and the thread release element 14 is introduced from below into the centrifugal spinning element 3, as represented in Figure 3C. As soon as the cutting edge 16 of the thread release element 14 touches the winding cone 22 of the spinning cake 15 deposited at the inner wall 25 of the centrifugal spinning element 3, this is re-reeled onto the re-reeling sleeve 9 on account of the rotation of the centrifugal spinning element 3. The thread guide contour 17 on the thread release element 14 prevents the thread release element 14 also being accidentally rewound. After the thread release element 14 was withdrawn, the spinning cop 36, as indicated in Figure 3E, is moved by moving the thread guide tube 7 to a stop 37 into a doffing position in which the spinning cop 36 can be taken over by a transport device 38 and can be transported away for further processing. The invention is not restricted to the exemplified embodiments described above. Rather, further embodiments can be envisaged within the scope of the general concept of the invention. For example, it is altogether possible, even with a regular spinning end, to move the thread guide tube 7 at "normal" traversing speed into the upper dead centre 31, then to stop the traversing and with the introduction of the re- reeling sleeve 9 into the re-reeling position 34 to wait slightly, as indicated in Figure 4C. Another refinement indicated in Figure 4B provides moving the last upward traversing motion 32 of the thread guide tube 7 at "normal" traversing speed and subsequently adding some additional, short traversing travels 40 in the region of the upper dead centre. 18 We claim: 1. A method for operating a spinning device comprising a centrifugal spinning element rotating at high speed and also a thread guide tube dipping into the centrifugal spinning element having a re-reeling tube displacebly disposed on the thread guide tube, whereby the thread guide tube performs, relative to the centrifugal spinning element, a traversing travel and a superimposed advancing movement downwards and in so doing deposits a yarn package with a cop winding on the inner wall of the centrifugal spinning element characterized in that before introducing the rewinding process, the thread guiding tube (7) is brought by a drive (8) to a rewinding position (31) that is respectively dependant on the last lower dead point of the traverse stroke of the thread guiding tube (7), whereby the last traverse stroke of the thread guider (7) always runs upwards in the direction of the rewinding position (31), after the thread guiding tube (7) is lower by a defined stretch; the stinking rewinding sleeve (9) introduces the rewinding process; and after completion of the rewinding process the thread guiding tube (7) is driven to pre-determined lower position and thereby the spinning cop (36) generated by the rewinding process is shifted to a defined doff position. 2. A method as claimed in claim 1, wherein at least at the end of a regular spinning process the speed at which the re-reeling sleeve is lowered is matched to the vertical thread unwinding speed predetermined by the traversing motion of the thread guide tube. 3. A method as claimed in claim 2, wherein the traversing motion of the thread guide tube takes place in the direction of the re-reeling position at a traversing speed which is significantly lower that a customary traversing speed during the spinning process. 4. A method as claimed in claim 2, wherein the traversing motion of the thread guide tube in the direction of the re-reeling position takes place at regular traversing speed, in that the thread guide tube then stays in the region of the re- reeling position, and in that then, with a time delay, the feed of the re-reeling sleeve takes place to initiate the re-reeling process. 5. A method as claimed in claim 2, wherein the traversing motion of the thread guide tube in the direction of the re-reeling position takes place at customary traversing speed, in that the thread guide tube then performs a few additional, short traversing travels in the region of the re-reeling and in a time delay the feed of the re-reeling sleeve takes place to initiate the re-reeling process. 6. A method as claimed in claim 1, wherein the re-reeling sleeve is lowered by a distance for which the height of the winding cone of the yarn package, the setback of the re-reeling sleeve and also the length of the unwound lower end of the re-reeling sleeve is taken into consideration. 7. A method as claimed in claim 6, wherein the distance preferably has a length of roughly 50 mm. 8. A method as claimed in claim 6, wherein the re-reeling sleeve is lowered to such an extent that the lower edge of the re-reeling sleeve with respect to the lower edge of the winding cone of the yarn package always has a constant distance that determines the length of the lower, free sleeve end of the re- reeling sleeve. 9. A method as claimed in claim 8, wherein the re-reeling sleeve is lowered so that the length of the lower, free sleeve end is roughly 15 mm. 10. A method as claimed in claim 1, wherein the length of the yarn package is chosen so that it is optimally matched to the useable inner length of the centrifugal spinning element, with the necessary length of the re-reeling sleeve simultaneously being minimised. 11. A method s claimed in claim 10, wherein a yarn package is established whose maximum length is the inner length of the centrifugal spinning element minus two safety distances at the end. 12. A method as claimed in claim 11, wherein the length of the safety distances at the end is respectively roughly 5 mm. 13. A method as claimed in claim 11, wherein a are-reeling sleeve is used, the length of which is produced from the maximum length of the yarn package plus two free sleeve ends at the ends. 14. A method as claimed in claim 1, wherein the traversing speed of the thread guide tube, the reaction time of the sensor detecting a thread breakage and the setback of the re-reeling sleeve are matched to one another. A method for operating a spinning device comprising a centrifugal spinning element rotating at high speed and also a thread guide tube dipping into the centrifugal spinning element having a re-reeling tube displacebly disposed on the thread guide tube, whereby the thread guide tube performs, relative to the centrifugal spinning element, a traversing travel and a superimposed advancing movement downwards and in so doing deposits a yarn package with a cop winding on the inner wall of the centrifugal spinning element characterized in that before introducing the rewinding process, the thread guiding tube (7) is brought by a drive (8) to a rewinding position (31) that is respectively dependant on the last lower dead point of the traverse stroke of the thread guiding tube (7), whereby the last traverse stroke of the thread guider (7) always runs upwards in the direction of the rewinding position (31), after the thread guiding tube (7) is lower by a defined stretch; the stinking rewinding sleeve (9) introduces the rewinding process; and after completion of the rewinding process the thread guiding tube (7) is driven to pre-determined lower position and thereby the spinning cop (36) generated by the rewinding process is shifted to a defined doff position. |
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| Patent Number | 224721 | ||||||||||||
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| Indian Patent Application Number | 01524/KOLNP/2004 | ||||||||||||
| PG Journal Number | 43/2008 | ||||||||||||
| Publication Date | 24-Oct-2008 | ||||||||||||
| Grant Date | 22-Oct-2008 | ||||||||||||
| Date of Filing | 12-Oct-2004 | ||||||||||||
| Name of Patentee | SAURER GMBH & CO. KG. | ||||||||||||
| Applicant Address | LANDGRAFENSTRASSE 45, D-41069 MONCHENGLADBACH | ||||||||||||
Inventors:
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| PCT International Classification Number | D01H 9/06, 1/08 | ||||||||||||
| PCT International Application Number | PCT/EP2003/02805 | ||||||||||||
| PCT International Filing date | 2003-03-18 | ||||||||||||
PCT Conventions:
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