Patent Application
20250002291
The invention relates to a thread guide device for the winding apparatus of a workstation of a textile machine producing cross-wound bobbins, wherein the winding apparatus has a bobbin drive roller for rotating a cross-wound bobbin, and also a thread traversing device for traversing a thread running onto the surface of the cross-wound bobbin.
Thread traversing devices have long been known in connection with winding apparatuses of workstations of textile machines producing cross-wound bobbins, e.g., rotor spinning machines or cross-winding machines, and are described in various embodiments in the patent literature. Such thread traversing devices are generally used for traversing a thread running onto the surface of a rotationally driven cross-wound bobbin, wherein a thread traversing triangle is produced. However, if no corresponding countermeasures are taken, there are constantly differences in the thread length of the running thread during the winding process with such thread traversing triangles, which differences in thread length often have a very negative effect on the cross-wound bobbins to be produced.
In order to minimize such differences in thread length, i.e., to keep the differences in thread length that occur in the region of the thread traversing triangles when winding cross-wound bobbins as low as possible, various thread guide devices for thread traversing devices have already been developed in the past.
However, the known winding apparatuses of the workstations of rotor spinning machines or air-jet spinning machines and of cross-winding machines can differ considerably both in terms of how their thread traversing device is embodied and in terms of how their thread guide device is embodied.
For example, DE 42 23 835 A1 and/or DE 43 30 647 A1 show and describe winding apparatuses the thread traversing devices of which are each formed by a circulating endless belt that is loaded with thread entrainment means and can be driven by a single motor. The thread entrainment means traverse the running thread between two thread transfer points arranged at the end of the traversing region in each case. A thread guide device is also installed in each case upstream of the thread traversing devices and extends over the length of the traversing region, and is formed, for example, by a stationary sheet metal element which has a convexly running, rounded thread guide edge.
A comparable winding apparatus, which, however, differs somewhat in the details from the above-described winding apparatuses, is known from DE 100 51 997 A1. This known winding apparatus uses a thread guide as a thread traversing device, which thread guide is fastened to an alternately drivable toothed belt. A thread guide device, which in the present case is designed as a convexly curved round rod, is installed somewhat upstream of the thread guide of this thread traversing device.
DE 10 2007 018 660 A1 furthermore discloses a winding apparatus which uses as a thread traversing device a finger thread guide that can be driven by a single motor. Upstream of the finger thread guide, a thread guide device is installed which is formed by a sheet metal element having a convexly curved thread slide surface. The thread slide surface of the thread guide device extends in a straight line in the direction of the running thread.
While it was possible to somewhat reduce the differences in the thread length of a running thread, which occur during the production of cross-wound bobbins in the region of the thread traversing triangle, with the thread guide devices described above, the known thread guide devices are not yet fully developed and can certainly be improved.
Proceeding from the above-described prior art, the object of the invention is to develop a thread guide device which prevents differences in the thread length of a running thread in the region of the thread traversing triangle from occurring during the winding of cross-wound bobbins.
This object is achieved according to the invention by a thread guide device having a spherically designed thread slide surface.
Advantageous embodiments of the thread guide device according to the invention are the subject matter of the dependent claims.
The advantage of the thread guide device according to the invention is, in particular, that the thread lengths between a thread guide point and a cross-wound bobbin, or the thread lengths in the thread traversing triangle are evened out during the winding process. This means that the thread length existing between the thread guide contours of the thread guide of a thread traversing device and the thread guide point when the thread guide is positioned centrally and the thread length which arises between the thread guide contours of a thread guide and of the thread guide point when the thread guide is in one of its two end positions is almost the same, with the result that the formation of thread tension peaks is largely prevented during the winding process.
Moreover, the use of a thread guide device with a spherically shaped thread slide surface not only allows for precise adjustment of the desired traverse width of the cross-wound bobbin, but also reduces the traverse shortening occurring during bobbin travel. This means that cross-wound bobbins that are wound with a thread guide device designed according to the invention have a more uniform flank appearance and thus more yarn material compared to cross-wound bobbins that have been wound with a thread guide device with a conventional guide contour.
In an advantageous embodiment, it is provided for the specific shaping of the spherical thread slide surface of the thread guide device to be independent of the width of the cross-wound bobbins to be produced. This means that, although the thread length changes to be compensated for in a thread traversing triangle during the winding process are dependent upon the width of the cross-wound bobbin to be produced, it is not necessary to use a thread guide device that has a relatively clearly shaped, spherical thread slide surface when producing wide cross-wound bobbins, or to use thread guide devices the spherical thread slide surface of which is less pronounced when producing narrower cross-wound bobbins. However, it may be advantageous to use a geometry variation of the spherical design, depending upon yarn titer, yarn property, and/or the material combination of the yarn to be processed.
Advantageously, the thread guide devices are each arranged directly in front of the thread traversing devices. In this way, the thread pulled off the spinning cop and running onto the surface of the cross-wound bobbin during the winding process is reliably prevented from accidentally slipping off the thread guide contours of the thread guide, which are designed, for example, in a fork-like manner.
As already indicated above, the thread pulled off the spinning cop and running onto the surface of the cross-wound bobbin forms, initiated by the thread traversing device, a thread traversing triangle upstream of the last thread guide point of the workstation during the winding operation. The last thread guide point can be the thread tension sensor. It is also conceivable within the scope of the invention for the last thread guide point to be formed by an eyelet or the like.
The thread traversing triangle has three corner points, wherein a first corner point lies in the region of the thread guide point, and the two other corner points are predetermined by the thread guide contours of a thread guide that can be driven by a single motor and is, in each case, positioned in one of its end positions. This means that the thread unwound from the spinning cop is alternately displaced to corner points by the thread guide contours of the thread guide after passing through the thread guide point, wherein the spherically designed thread slide surface of the thread guide device prevents thread length changes from occurring at all positions of the thread guide of the running thread.
In an advantageous embodiment, the thread guide device is made of stainless steel. Such stainless steel construction is not only very corrosion-resistant, but also relatively abrasion-resistant. This means that such thread guide devices made of stainless steel and equipped with a spherically designed thread slide surface are characterized by a long service life. It is also conceivable for the thread guide device to be made of another material. It is essential to the invention that the thread guide device have good sliding properties and good abrasive and chemical resistance.
Preferably, the thread guide devices are each fastened to a workstation housing of a workstation so as to be demountable. That means that the thread guide device can be dismantled quickly and easily, if necessary, and can be replaced, for example, by a thread guide device having a thread slide surface that is more spherical.
According to a preferred embodiment, the workstation is a winding station of a cross-winding machine or a spinning station of a spinning machine.
The thread guide device moreover has mounting devices, in/on which thread guide pins can be fastened, which reliably prevent the running thread from sliding off the spherically designed thread slide surface of the thread guide device during the winding process. The mounting devices allow not only for easy, precise adjustment of the distance of the thread guide pins, but also for a correction of this distance at any time, if necessary.
Further details of the invention can be gathered from an exemplary embodiment shown below with reference to drawings.
In the drawings:
For supplying the workstations 2 with fresh spinning cops 3 or for disposing the empty sleeves 17 unwound at the workstations 2, such cross-winding machines 1 often have a sleeve and bobbin transport system 6, in which transport plates 11—so-called peg trays—equipped with spinning cops 3 or empty sleeves 17 circulate. Of such a sleeve and bobbin transport system 6, only the cop feed line 24, the reversibly drivable storage section 25, the transverse transport paths 26 leading to the workstations 2 and each equipped with an unwinding position UP, and the sleeve return line 27 are shown in
The workstations 2 of such cross-winding machines 1 are also known to be equipped with various handling and sensor devices which enable smooth operation of the workstations 2—in particular, the production of proper cross-wound bobbins 5—during the winding process. One of these handling devices of the workstations 2 is, for example, the winding apparatus denoted by reference number 4, which has a bobbin frame 8, mounted so as to be movable about a pivot axis 12, for holding a cross-wound bobbin 5 in a freely rotatable manner. As illustrated, the cross-wound bobbin 5 rests with its surface on a bobbin drive roller 9 during the regular winding process and is entrained by the latter via frictional engagement. The bobbin drive roller 9 is connected, for example, to a single electric motor drive 22, which is in communication with a workstation computer 28 via a control line 18.
A thread traversing device 10 is provided for traversing the thread 16 pulled off a spinning cop 3 and running onto the cross-wound bobbin 5 during the winding process, which thread traversing device continuously traverses the thread 16 between the two face sides of the cross-wound bobbin 5. The thread traversing device 10 is equipped with a thread guide 13—preferably a finger thread guide in this exemplary embodiment-which is acted upon by an individual drive 14 that is connected to the workstation computer 28 via a control line 15.
Furthermore, a thread guide device 23 designed according to the invention is arranged directly upstream of the thread guide 13 of the thread traversing device 10, which thread guide device 23 will be explained in more detail below with reference to
Each of the workstations 2 of such a cross-winding machine 1 also has a pivotably mounted suction nozzle 19, to which negative pressure can be applied, for handling the so-called upper thread, a pivotably mounted gripper tube 20, to which negative pressure can be applied as well, for handling the lower thread, and a pneumatic thread splicing device 21, by means of which, if necessary (for example, after thread breakage), the thread ends of the upper and lower threads can be combined again almost in a yarn-like manner.
The workstations 2 of such cross-winding machines 1 are also generally often equipped with further devices—for example, a lower thread sensor 29, a thread tensioner 30, an electronic thread cleaner 31, a thread cutting device 32, a waxing device 33, and a thread tension sensor 34. These devices are also connected to the workstation computer 28 via control and signal lines.
As is known, the electronic thread cleaner 31 performs constant quality monitoring of the running thread 16 during the rewinding process. This means that the thread cleaner 31 continuously monitors the thread 16 passing through it and thereby detects serious thread defects, such as thread breakage, double threads, and thin or thick spots.
During the rewinding process, the running thread 16 is moreover generally scanned by a thread tension sensor 34 which is arranged in the thread path upstream of the thread traversing device 10.
As indicated, the running thread 16 traversed by the thread guide 13 forms a thread traversing triangle 36 having corner points A, B, and C during the winding process. Corner point A lies on the output side of the thread guide 42 of a thread guide point 34 arranged upstream of the thread guide device 23 in the thread path, which thread guide point 34 is formed by the thread tension sensor in this exemplary embodiment. Corner points B or C are predetermined by the thread guide contours 37 or 38 of the thread guide 13 positioned in one of its predeterminable end positions.
Rotor spinning machines or air-jet spinning machines, which are likewise used for producing cross-wound bobbins 5, also have workstations 2 with such winding apparatuses 4.
The thread guide devices 23 moreover have mounting devices 40 for fastening thread guide pins 41, wherein the mounting devices 40 are designed such that the clear width W of the thread guide pins 41 can be adjusted as needed, wherein the distance W of the thread guide pins 41 can be corrected at any time. This means that, during the winding process, the thread guide pins 41 reliably prevent the thread 16 running onto the cross-wound bobbin 5 from slipping off the spherically designed thread slide surface 35 of the thread guide device 23.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2021 129 226.3 | Nov 2021 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2022/081280 | 11/9/2022 | WO |
