Title of Invention

METHOD AND DEVICE FOR OPERATING A WORK STATION OF A TEXTILE MACHINE THAT PRODUCES CROSS-WOUND BOBBINS

Abstract

The invention relates to a method and device for operating a work station (2) of a textile machine (1) that produces cross-wound bobbins, comprising: a creel (8) for rotationally holding a cross-wound bobbin (5); a thread laying device (10) for cross-winding a thread (16) being wound onto the cross-wound bobbin (5), and; a device which, in the event of an interruption in winding, prevents the thread end joined to the cross-wound bobbin to come next to the surface of the cross-wound bobbin. The invention provides that the drive (14) of the thread lying device is controlled by a winding head computer (28) in such a manner that the thread guide (13) of the thread laying device (10), in the event of an interruption in winding, is immediately moved into a position in which it is ensured that the thread end joined to the cross-wound bobbin (5) reliably winds onto the surface of the cross-wound bobbin (5).

Full Text

FORM 2 THE PATENT ACT 1970 (39 of 1970) & The Patents Rules, 2003 COMPLETE SPECIFICATION (See Section 10, and rule 13) TITLE OF INVENTION METHOD AND DEVICE FOR OPERATING A WORK STATION OF A TEXTILE MACHINE THAT PRODUCES CROSS-WOUND BOBBINS APPLICANT(S) a) Name b) Nationality c) Address SAURER GMBH & CO., KG. GERMAN Company LANDGRAFENSTRASSE 45, D-41069 MONCHENGLADBACH, GERMANY PREAMBLE TO THE DESCRIPTION The following specification particularly describes the invention and the manner in which it is to be performed : - Description The invention relates to a method for operating a workstation of a textile machine that produces cross-wound bobbins according to the preamble .of claim 1 and a device according to claim 5. When producing a textile bobbin, as is known, at least two conditions have to be satisfied, on the one hand, the relevant textile bobbin has to be rotated and, on the other hand, the thread running onto the bobbin has to be traversed along the bobbin axis. By relatively rapid traversing of the thread, in this case, a so-called cross-wound bobbin can be produced, which is not only distinguished by a relatively stable bobbin body, but also by good run-off behaviour. In modern, textile machines that produce cross-wound bobbins, for example automatic cross-winding machines, which operate at high winding speeds, the traversing speed of the thread transfer devices is therefore also very high. Various thread transfer systems are known from automatic cross-winding machines to generate the traversing movements of the running-on thread. So-called thread guiding drums, which generally also bring about the peripheral drive for the cross-wound bobbin, are very widespread, for example. Thread guiding drums of this type have the disadvantage, however, that regardless of the bobbin diameter, the same transfer angle is always provided and this results in the occurrence of so-called winding patterns, which can lead to considerable problems during later unwinding in certain rotational speed conditions between the bobbin and drive drum if no particular measures are taken. Moreover, with thread guiding drums of this type, there is always the risk, in the event of an interruption in winding, in particular in the event of a thread breakage or a controlled clearer cut, of the thread end connected to the cross-wound bobbin, the so-called upper thread, not running onto the surface of the cross-wound bobbin, but falling next to the thread guiding drum. Such threads positioned after a thread breakage next to the thread guiding drum are 2 often called a falling thread. As falling threads of this type can no longer be handled by the thread suction nozzle of the winding head and therefore require a manual intervention of the operating personnel, falling threads of this type should be avoided as far as possible. In order to be able to generate a predetermined winding pattern, for example a precision or step precision winding, it has moreover been known for a long time to separate the rotation of the cross-wound bobbin and the thread transfer device in terms of drive technology. In these known devices, the cross-wound bobbin held in a creel rests on a drive roller, for example, which can be driven in a defined manner by an associated drive and entrains the cross-wound bobbin during the winding process via frictional engagement. The associated thread transfer device also has its own drive, in this case. A thread transfer device is described, for example, in DE 198 58 548 Al, the finger thread guide of which is driven by an electromagnetic drive. The size and direction of the drive torque of the thread guide drive is adjusted, in this case, by controlling or regulating the current supplied in each phase of the movement. This takes place by means of a control computer, preferably the winding head computer, which control is the current intensity and current direction according to a predeterminable programme as a function of the angle and time. In this manner, for example, the respectively desired transfer angle of the thread, the traversing width and the traversing end points can be adjusted in each case. The respective angle position of the thread guide finger is detected, adherence to the desired value is checked and, if necessary, the actual value is adapted to the desired value by regulating, by means of a corresponding sensor system, preferably an angle sensor. Finger thread guides of this type have proven to be extremely flexible thread transfer devices, but, like thread guiding drums, have the disadvantage that in the event of an interruption in winding, in particular in the event of a thread breakage, but also 3 in the event of a controlled clearer cut, the risk always exists of the upper thread connected to the cross-wound bobbin not running onto the cross-wound bobbin in a proper manner. In other words, in the known thread transfer systems, there is always a risk of the free thread end falling next to the end faces of the cross-wound bobbin and it then no longer being possible, or not in a proper manner, for it to be picked up by the thread suction nozzle of the winding head. Devices have therefore already been developed in the past, in which falling threads were to be avoided, for example, by a clearer cut being implemented in a delayed manner only at a point in time when the thread is traversed by the thread guiding drum in the direction of the bobbin centre. Devices of this type described in DE 40 25 696 Al or EP 0 631 962 Bl are, however, generally ineffective in the event of thread breakages, which occur as is known, in a completely uncontrolled manner. In other words, in these known devices, there continues to be a risk in the event of a thread breakage, that falling threads will occur, which cannot be handled by the thread suction nozzle. Furthermore, a winding head of a textile machine that produces cross-wound bobbins is described in EP 0 814 045 A2, in which a thread guiding device which can be activated in a defined manner is arranged in the region of the thread guiding drum. This known thread guiding device has two pivotably mounted, pneumatically actuable thread guiding arms, which, for example, when the thread tension decreases, can be pivoted in the direction of the bobbin centre. The inwardly pivoting thread guiding arms are intended, in this case, to guide the upper thread connected to the cross-wound bobbin to the bobbin centre and thereby avoid falling threads being produced. The known device is relatively complex, however, with regard to its design structure, in other words, the device takes up a relatively large amount of space. In view of the space conditions, which are restricted in any case, in the region of the 4 winding devices of winding heads of this type, the known device is therefore not an optimum solution for overcoming the problem of "falling threads". Proceeding from the aforementioned prior art, the invention is based on the object of developing a method and a device which makes the operation of the workstations of a textile machine that produces cross-wound bobbins more reliable and with which, in particular, the development of falling threads can be easily avoided. This object is achieved according to the invention by a method as described in claim 1 and by a device according to claim 5. Advantageous embodiments of the device according to the invention are described in the sub-claims 1 to 4. The method according to the invention described in claim 1 for operating a workstation of a textile machine that produces cross-wound bobbins has, in particular, the advantage, that with a method of this type, easily and without the region of the winding device becoming inaccessible owing to additional devices, the development of falling threads can be avoided in the event of the occurrence of interruptions in winding. In other words, owing to the immediate moving of the thread guide into a predetermined, advantageous position, it is ensured that even in the event of a thread breakage, falling threads, the elimination of which would necessitate a manual intervention by the operating personnel, do not occur. As described in claims 2 and 3, method steps have proven advantageous, in which the thread guide, both on the occurrence of a surprising thread breakage, and also when a controlled clearer thread is initiated, is immediately moved into a position which is central with respect to the cross-wound bobbin. In other words, in the event of a winding interruption, the traversing stroke of the thread guide is either immediately stopped in the bobbin centre or the direction of the traversing stroke, is 5 immediately changed into the direction of the bobbin centre and the thread guide is then stopped there. Owing to this immediate, extremely rapid positioning of the thread guide in the bobbin centre it is ensured that the upper thread, after an interruption in winding, always runs reliably onto the surface of the cross-wound bobbin and can then be picked up again without any problems by the thread suction nozzle. In an alternative method step described in claim 4, it is provided that on the occurrence of a thread defect, the initiation of a controlled clearer step is delayed until it is ensured mat the finger thread guide is in its predetermined position, in other words in the bobbin centre. In a case such as this, when the thread clearer detects a thread defect, for example a thin or thick point, the thread guide is firstly properly positioned by its drive and only then is the necessary clearer cut triggered. As shown in claim 5, to carry out the method according to the invention, the device substantially comprises a finger thread guide, which is driven by an electromagnetic drive, an angle sensor for detecting the respective position of the thread guide finger, a thread clearer for detecting an interruption in winding and a control computer, for example a winding head computer. Both the electromagnetic drive of the finger thread guide and the angle sensor and the thread clearer are connected, in mis case, via control or signal lines to the control computer. As the above-described components are those required for proper operation of the winding head and therefore are present in any case, the additional outlay, which is required in order to be able to carry out the method according to the invention, is substantially reduced to slightly supplementing the control computer in terms of hardware and programming it accordingly. In other words, the outlay necessary to carry out the method according to the invention, is kept within narrow limits both in terms of hardware and software. 6 The invention will be described in more detail below with the aid of an embodiment shown in the drawings, in which: Fig. 1 schematically shows a winding head of a textile machine that produces cross-wound bobbins, comprising a cross-wound bobbin driven by a single motor at its periphery and a separate thread guide driven by a single motor, Fig. 2 shows a front view of a winding head of a textile machine that produces cross-wound bobbins with the devices required to carry out the method according to the invention. Fig. 1 schematically shows a side view of a winding head 2 of a textile machine 1 that produces cross-wound bobbins, in the present case a so-called automatic cross-winding machine. Automatic cross-winding machines 1 have, as known, a large number of winding heads 2 of this type between their end frames (not shown). On these winding heads 2, as also known and therefore not described in more detail, the spinning cops 3 produced on an upstream ring spinning machine are rewound to form large-volume cross-wound bobbins 5, which after their production, are transferred by means of a service unit (not shown), for example a cross-wound bobbin changer, to a cross-wound bobbin transporting device 7 along the length of the machine and are transported to a bobbin loading station or the like arranged at the end of the machine. Automatic cross-winding machines 1 of this type often also have a logistics device in the form of a bobbin and tube transporting system 6. The spinning cops 3 or empty tubes revolve on this bobbin and tube transporting system 6. Of the bobbin and tube transporting system 6, only the cop supply section 24, the storage section 25 which 7 can be driven so as to reciprocate, one of the transverse transporting sections 26 leading to the winding heads 2 and the tube return section 27 are shown in Fig. 1. The individual winding heads 2, as known and therefore only indicated, in each case, have various devices, which ensure proper operation of workstations of this type. One of these devices is, for example, the winding device characterised by the reference numeral 4, which has a creel 8 which is movably mounted about a pivot pin 12. In the present case, the cross-wound bobbin 5 rests during the winding process with its surface 31 on a drive roller 9 and is entrained thereby by frictional engagement. In an alternative embodiment, the cross-wound bobbin may also, however, be driven via a drive device which can be regulated with regard to rotational speed, preferably an electronically commutatable direct current motor, which is arranged directly on the creel 8 or is integrated into the creel 8. The thread 16 is traversed during the winding process by a thread transfer device 10. A thread transfer device 10 of this type indicated only schematically in Fig. 1 has a finger-like thread guide 13, which is driven by an electromechanical drive 14, as indicated in Fig. 2 and traverses the thread 16 between the two end faces 32 of the cross-wound bobbin 5. As can also be seen from Fig. 2, the drive 14 has a motor shaft 33, on which the finger-like thread guide 13 is non-rotatably arranged. On the side of the drive 14 opposing the thread guide 13, preferably protected under a removable covering cap, an angle sensor 17 is fitted, the structure of which is described in detail in DE 103 54 587 Al. 8 The winding head 2 also has a thread clearer 22, which is connected to the winding head computer 28 via a signal line 29 and via a thread cutting device 23, which is arranged in the region of the thread clearer 22 and which can be activated via a line 30 by the winding head computer 28. In an advantageous embodiment, a thread tensile force sensor 20 is also provided and is connected via a signal line 21 to the winding head computer 28. Sequence of the method according to the invention: As indicated in Fig. 2, during the regular winding operation a thread 16 is unwound from a spinning cop 3 arranged on a transporting plate 11 and positioned in an unwinding position in the region of the transverse transporting section 6 and wound onto a large-volume cross-wound bobbin 5, which is rotatably held between the bearing arms of a creel 8 during the winding process. The cross-wound bobbin 5, in this case, rests with its surface 31 on a drive roller 9. The drive roller 9 can be activated in a defined manner by an electromagnetic drive 34, which is connected via a control line 19 to the winding head computer 28 and entrains the cross-wound bobbin by frictional engagement. The thread 16, on its way to the cross-wound bobbin 5, crosses at least one thread clearer 22 and a thread cutting device 23. The running thread 16, which is monitored by the thread clearer 22 for thread defects, generates, in the thread clearer 22, inter alia a dynamic thread running signal, which is transmitted to the winding head computer 28 via the signal line 29. If this dynamic thread running signal is absent, for example because of a thread breakage, the winding head computer 28, which is always informed about the instantaneous position of the thread guide finger via the connected angle sensor 17, activates the drive 14 of the finger thread guide 13 via the control line 15 in such a way that the finger thread guide 13 is transferred as rapidly as possible into the position M, which 9 is located in the centre of the cross-wound bobbin. In other words, the finger thread guide 13 is already in the position M when the upper thread runs onto the cross-wound bobbin 5. Owing to the rapid positioning of the thread guide finger, it can be ensured that, even after a thread breakage, the thread end of the upper thread connected to the cross-wound bobbin 5 is always in a region, in which it can be reached by the thread suction nozzle 35 of the winding head 2. The thread suction nozzle 35 can therefore pick up the upper thread from the surface 31 of the cross-wound bobbin 5 without problems and transfer it to a thread splicing device 36, where the thread end of the upper thread is connected to the thread end of a lower thread, which a gripper tube 37 dedicated to the winding head has brought After the splicing of the thread ends of the upper and lower thread, the regular winding process is continued. 10 WE CLAIM: 1. Method for operating a workstation of a textile machine that produces cross- wound bobbins, comprising a creel for rotatably holding the cross-wound bobbin, a thread transfer device for traversing a thread running onto the cross-wound bobbin and a device, which prevents the thread end connected to the cross-wound bobbin from being able to arrive next to the surface of the cross-wound bobbin in the event of an interruption in winding, characterised in that the drive of the thread transfer device is activated by a winding head computer in such a way that the thread guide of the thread transfer device, in the event of an interruption in winding, is immediately displaced into a position in which it is ensured that the thread end connected to the cross-wound bobbin reliably runs onto the surface of the cross-wound bobbin. 2. Method according to claim 1, characterised in that, in the event of a thread breakage, the thread guide is immediately displaced into a position which is central with respect to the cross-wound bobbin. 3. Method according to claim 1, characterised in that on initiation of a controlled clearer cut, the thread guide is immediately displaced into a position which is central with respect to the cross-wound bobbin. 4. Method according to claim 1, characterised in that, after the detection of a thread defect, the initiation of a controlled clearer cut is delayed until the thread guide is positioned in a position which ensures that the thread end connected to the cross-wound bobbin reliably runs onto the surface of the cross-wound bobbin. 11 5. Device for carrying out the method according to claim 1, characterised in that the thread transfer device has a finger thread guide (13) with an electromagnetic drive (14), an angle sensor (17) for detecting the respective position of the finger thread guide (13), a sensor device (20, 22) for detecting an interruption in winding, and a control computer (28), in that the electromagnetic drive (14), the angle sensor (17) and the sensor device (20,22) are connected to the control computer (28) and in that in the event of an interruption in winding, the drive (14) of the finger thread guide (13) can be activated by the winding head computer (28) in such a way that the finger thread guide (13) is positioned in a position, which ensures that the thread end connected to the cross-wound bobbin (5) runs onto the surface (31) of the cross-wound bobbin (5). Dated this 2nd day of March, 2007 12

Documents:

315-MUMNP-2007-ABSTRACT(12-12-2008).pdf

315-mumnp-2007-abstract(granted)-(29-5-2009).pdf

315-mumnp-2007-cancelled pages(24-5-2007).pdf

315-MUMNP-2007-CLAIMS(12-12-2008).pdf

315-MUMNP-2007-CLAIMS(CANCELLED PAGES)-(12-12-2008).pdf

315-mumnp-2007-claims(complete)-(2-3-2007).pdf

315-mumnp-2007-claims(granted)-(29-5-2009).pdf

315-mumnp-2007-claims.doc

315-mumnp-2007-claims.pdf

315-mumnp-2007-correspondance-received.pdf

315-MUMNP-2007-CORRESPONDENCE(12-12-2008).pdf

315-mumnp-2007-correspondence(24-5-2007).pdf

315-mumnp-2007-correspondence(ipo)-(23-6-2009).pdf

315-mumnp-2007-correspondence-others.pdf

315-mumnp-2007-correspondence-received.pdf

315-mumnp-2007-description (complete).pdf

315-MUMNP-2007-DESCRIPTION(COMPLETE)-(12-12-2008).pdf

315-mumnp-2007-description(complete)-(2-3-2007).pdf

315-mumnp-2007-description(granted)-(29-5-2009).pdf

315-MUMNP-2007-DRAWING(12-12-2008).pdf

315-mumnp-2007-drawing(complete)-(2-3-2007).pdf

315-mumnp-2007-drawing(granted)-(29-5-2009).pdf

315-mumnp-2007-drawings.pdf

315-MUMNP-2007-FORM 1(2-3-2002).pdf

315-mumnp-2007-form 1(2-3-2007).pdf

315-mumnp-2007-form 1(24-5-2007).pdf

315-mumnp-2007-form 2(12-12-2008).pdf

315-mumnp-2007-form 2(complete)-(2-3-2007).pdf

315-mumnp-2007-form 2(granted)-(29-5-2009).pdf

315-MUMNP-2007-FORM 2(TITLE PAGE)-(12-12-2008).pdf

315-mumnp-2007-form 2(title page)-(complete)-(2-3-2007).pdf

315-mumnp-2007-form 2(title page)-(granted)-(29-5-2009).pdf

315-mumnp-2007-form 3(2-3-2007).pdf

315-mumnp-2007-form 5(2-3-2007).pdf

315-mumnp-2007-form-1.pdf

315-mumnp-2007-form-18.pdf

315-mumnp-2007-form-2.doc

315-mumnp-2007-form-2.pdf

315-mumnp-2007-form-26.pdf

315-mumnp-2007-form-3.pdf

315-mumnp-2007-form-5.pdf

315-mumnp-2007-form-pct-isa-220.pdf

315-mumnp-2007-form-pct-isa-237.pdf

315-mumnp-2007-form-pct-ro-101.pdf

315-mumnp-2007-pct-search report.pdf

315-mumnp-2007-wo international publication report(2-3-2007).pdf

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