Patent Publication Number: US-2023150790-A1

Title: Traversing thread guide

Description:
The invention relates to a traversing thread guide for causing a thread to traverse at a workstation of a textile machine that produces cross-wound packages, comprising
         a base carrier, which can be arranged on a traversing rod, and   a thread-guiding element, which is arranged on the base carrier and which has two wall portions, which are arranged at a distance from each other and delimit a thread insertion slot and a thread-guiding channel.       

     Traversing thread guides of the aforementioned type are known, in many designs, from the prior art. At the workstations of a textile machine that produces cross-wound packages, these traversing thread guides are used in order to wind a continuously fed thread evenly onto a rotated winding package, the thread being moved back and forth in the axial direction of the winding package by means of the traversing thread guide. For this purpose, the traversing thread guide performs an oscillating movement along a longitudinal axis of the traversing rod, adjacently to the surface of the winding package and parallel to the axis of the winding package, leading to uniform winding of the thread on the winding package. In order to receive the thread at the thread-guiding element of the traversing thread guide, the thread-guiding element has a thread insertion slot, via which the thread to be wound on the winding package enters the thread-guiding channel of the thread-guiding element, by means of which thread-guiding channel the thread is guided along the cross-wound package during the oscillating movement of the traversing thread guide. 
     For exact thread displacement and an even package build, it is important that the thread-guiding element is positioned as close as possible to the winding point, i.e. the point where the thread runs onto the package. As the winding duration increases and the package diameter grows, the nip region between a package drive roller and the take-up package is reduced, whereby the risk that the thread-guiding element touches or even gets caught on the cross-wound package is increased. Particularly in the case of softly wound packages or coarse yarns and conventional winding, the package surface is not perfectly smooth, but rather it has a wavy surface. In these cases, it is relatively easy for the front side of the thread-guiding element to touch the package surface, causing portions of the thread-guiding element to get caught in the package surface. This can result in damage to the take-up package or can even cause the take-up package to be pressed or ripped out of its holding frame. Furthermore, the holding frame, the thread-guiding element or the entire traversing thread guide can also be damaged; the traversing thread guide can be ripped off as a result of the transverse forces which act. 
     Proceeding therefrom, the invention addresses the problem of providing a traversing thread guide which ensures reliable thread displacement while avoiding the risk of catching on the package surface. 
     The invention solves the problem by means of a traversing thread guide having the features of claim  1 . Advantageous further developments of the invention are stated in the dependent claims. 
     The traversing thread guide according to the invention is characterised in that each of the wall portions has, on its top facing away from a base surface of the thread-guiding element, a support surface formed by a plane. 
     The wall portions are half-shell-shaped bodies which are connected to the base surface of the thread-guiding element and which extend over a region above the base surface of the thread-guiding element and which delimit a thread-guiding region between the base surface and the wall portions. The wall portions are spaced apart from each other—perpendicularly to the running direction of the thread through the thread-guiding channel—and thus form a thread insertion slot, via which the thread to be guided enters the thread-guiding channel which—with respect to the usage position—runs below the thread insertion slot. 
     According to the invention, the tops of the wall portions, which, in the usage position, face a cross-wound package, each have a support surface which is formed by a plane, i.e. all straight lines between any two points of the support surface lie completely in the same plane. 
     Because a flat support surface is formed on the thread-guiding element, a defined surface that can come into contact with the cross-wound package during winding operation is provided on the traversing thread guide. The flat design significantly reduces the risk that the thread-guiding element catches on the thread winding arranged on the cross-wound package. If the support surfaces contact the surface of the cross-wound package, the support surfaces reliably slide on the surface of the cross-wound package, even in the case of coarse windings, so that catching does not occur or the risk of catching is considerably minimised. By means of the basically freely selectable dimensioning of the support surface, trouble-free winding operation is thus ensured. 
     In principle, the orientation of the individual support surfaces of the two wall portions can be freely selected. Thus, arranging the support surfaces of the two wall portions in different planes is also possible in principle. However, according to a particularly advantageous embodiment of the invention, the support surfaces are arranged in a common plane. According to this further development of the invention, the two support surfaces of the mutually adjacent wall portions lie in a common plane, whereby a common support surface arranged at a uniform distance from the surface of the cross-wound package is formed, and this common support surface further reduces the risk of catching on a winding arranged on the cross-wound package, since the two support surfaces jointly form an overall support surface arranged at a uniform distance from the surface of the cross-wound package. 
     In addition to the dimensioning and form, the design of the support surfaces can also, in principle, be freely selected. According to an advantageous embodiment of the invention, the support surfaces are oriented parallel to the base surface of the thread-guiding element. This embodiment of the invention constitutes a particularly simple and economical design of the traversing thread guide which, when the traversing thread guide is appropriately arranged relative to the cross-wound package, reliably and effectively minimises the risk of catching in the thread winding on the cross-wound package. 
     According to another advantageous embodiment of the invention, the support surfaces are inclined relative to each other and/or toward an end face of the thread-guiding element, as an alternative to the parallel orientation of the support surfaces relative to the base surface according to an advantageous further development. 
     If the support surfaces are inclined relative to each other, the support surfaces fall or rise from their outer, lateral boundaries, which extend in the thread running direction, toward the thread insertion slot. That is, the support surfaces have a smaller or larger distance from the base surface in the region of the thread insertion slot than in the region of the outer side boundaries of the support surfaces. 
     In the case of inclination toward the end face, the distance of support surface from the base surface decreases in the thread running direction. By means of a corresponding design of the support surfaces, catching of the thread-guiding element on the cross-wound package is further prevented, since additionally regions which could penetrate, as a “tip”, into the surface of the cross-wound package are eliminated on the thread-guiding element. 
     In the case of an embodiment of the invention in which the support surfaces are inclined relative to each other, it is provided—according to a particularly advantageous embodiment of the invention—that the planes of the support surfaces intersect at an angle of more than 140°, preferably more than 160°, particularly preferably 175° to 195°. The specified angles are the angle that the planes of the support surfaces include. The slight inclination of the support surfaces that is produced by these angles further increases the protection against catching of the thread-guiding element. This protection can be increased further if, as is provided according to an advantageous further development of the invention, the tops of the wall portions are rounded in the region of their inner edges, front edges, side edges, secondary edges and/or rear edges, preferably with a radius of 0.3 to 7 mm, particularly preferably 0.3 to 4 mm. 
     The inner edges are the edges of the wall portions which are adjacent to each other and which delimit the thread insertion slot. The front edges are the edges of the wall portions which run in the transition region between the support surfaces and the end faces. The side edges run between the support surfaces and the side surfaces, which extend in the thread running direction. The thread-guiding element comprises secondary edges when, according to an advantageous embodiment, the thread-guiding element is provided with lateral and front transition portions on the wall portions, the secondary edges extending between these regions. The rear edges are the portions of the wall portions oriented opposite the thread running direction. Rounding of one or more edges further reduces the risk that the thread-guiding element catches on the surface of the cross-wound package. By means of the roundings, the regions that come nearest to the cross-wound package are designed overall such that they do not form a point of engagement for the thread arranged on the cross-wound package. 
     The design of the wall portions, in particular the form of the support surface in the region of the tops, can, in principle, be freely selected. The wall portions usually have at least a top, which is spaced apart from the base surface and comprises the support surface, and an end face and a side surface, which extend between the top and the base surface. According to another embodiment of the invention, the wall portions each have, in the region between the support surface and a side surface, a lateral transition portion which drops toward the side surface. The lateral transition portion is a portion which rises from the side surfaces toward the support surfaces and by means of which the thread-guiding element is further rounded, so that catching is particularly reliably avoided in the event of contact with the cross-wound package. 
     Similarly to the lateral transition portions, according to another embodiment of the invention it can be provided that the wall portions have, in the region between the end face and the side surface, front transition portions which taper the thread-guiding element toward the end face. Such front transition portions likewise reduce the region of contact of the thread-guiding element with the cross-wound package and further reduce the risk of catching. 
     According to another embodiment of the invention, it is also provided that the rear edges and the inner edges are connected to each other in a rounded manner. Overall, rounding, like the rounding of the rear edge and inner edge, is a supplementary measure for increasing the operational reliability of the traversing thread guide. 
     According to another embodiment of the invention, it is also provided that the tops have, in the region between the rear edge and the support surface, a rear transition portion inclined toward the base surface. The rear transition portion is the portion of the wall portion which is directed against the thread running direction and which likewise contributes, as a result of this embodiment, to preventing catching of the thread-guiding element. 
     In principle, the thread-guiding element can be integrally connected to the base carrier as a single piece or can be adhesively bonded to the base carrier, by means of which the traversing thread guide can be fastened to a traversing rod. According to another embodiment of the invention, the thread-guiding element is detachably connected to the base carrier. This allows the thread-guiding element to be produced from a material deviating from the material of the base carrier; for example, the thread-guiding element can be produced from a ceramic material which has good sliding properties and low wear properties. Furthermore, in the event of wear or damage, the thread-guiding element can be easily exchanged without the need for a complete exchange of the traversing thread guide. 
     In principle, the orientation of the end face relative to the base surface can be freely selected. However, according to an advantageous further development of the invention, the end face and the base surface include an angle of 75° to 90°, preferably 80°. According to this embodiment of the invention, the end face is particularly preferably slightly inclined toward the base surface. This orientation of the end face relative to the base surface further prevents catching of the traversing thread guide on the thread arranged on the cross-wound package. 
    
    
     
       An embodiment example of the invention is explained below with reference to the drawings. In the drawings: 
         FIG.  1    shows a schematic front view of a workstation of a textile machine that produces cross-wound packages, in the region of the cross-wound package; 
         FIG.  2    shows a perspective view of a traversing thread guide, comprising a base carrier and a thread-guiding element; 
         FIG.  3    shows a top view of the traversing thread guide of  FIG.  2   ; and 
         FIG.  4    shows a front view of the traversing thread guide of  FIG.  2   . 
     
    
    
       FIG.  1    shows a schematic illustration of a workstation of a textile machine that produces cross-wound packages, in the region of the cross-wound package  22 . Such textile machines generally have a plurality of workstations of the same type arranged next to each other in a row, in each of which a thread  24  is wound on a cross-wound package  22 . In the case of a twisting device (not shown), the thread  24  is transported toward the cross-wound package  22  and is wound on the cross-wound package  22 . On the way to the cross-wound package  22 , the thread  24  passes through different units, such as a thread sensor (not shown here), before the thread  24  runs onto the cross-wound package  22 , which is rotated by frictional engagement by means of a package drive roller  23 . The thread  24  running onto the cross-wound package  22  is made to traverse by a traversing thread guide  1 , which can be moved along a longitudinal axis of a traversing rod  21 , and said thread  24  runs onto the cross-wound package  22  in crossing windings. 
     The traversing thread guide  1  comprises a thread-guiding element  3 , which is made of a ceramic material, and a base carrier  4 , which is connected to the thread-guiding element  3  and by means of which the traversing thread guide  1  is detachably fastened to the traversing rod  21 . 
     The thread-guiding element  3  is arranged at the front end of the base carrier  4 , with respect to the thread running direction F, and comprises two wall portions  7 ,  8 , which are connected to a base surface  16  and are spaced apart from the base surface  16  in some parts in order to form a thread-guiding portion. The wall portions  7 ,  8  are arranged at a distance from each other perpendicularly to the thread running direction F so that inner edges  20  of the wall portions  7 ,  8 , which inner edges  20  extend in the thread running direction F and are adjacent to each other, form a thread insertion slot  2 , which is adjoined, toward the base surface  16 , by a thread-guiding channel  5  through which the thread  24  extends as the thread  24  is being wound on to the cross-wound package  22 , the thread  24  lying on the opposite sides of the thread-guiding channel  5  in alternation during the travel movement of the traversing thread guide  1  along the traversing rod  21 . 
     In the region of their tops, which, when the traversing thread guide  1  is in its installation position on the traversing rod  21 , face the cross-wound package  22 , the wall portions  7 ,  8  each have a support surface  9 , which is formed by a plane; in the embodiment example shown, the support surfaces  9  are arranged in a common plane. 
     The support surfaces  9  do not run parallel to the base surface  16  of the thread-guiding element  3 , but rather have an inclined orientation; the support surfaces  9  drop from their rear edges  11  to the front end faces  13  running transversely to the thread running direction F. 
     The wall portions  7 ,  8  also have a lateral transition portion  18 , which extends between the support surface  9  and the side surface  12  extending parallel to the thread running direction F. A front transition portion  17  on the wall portions  7 ,  8  connects the end faces  13  to the side surfaces  12 . The front transition portions  17  are inclined from the side surfaces  12  toward the thread-guiding channel  5 , such that the thread-guiding element  3  is tapered in the thread running direction F. In the rear region opposite from the end faces  13 , the wall portions  7 ,  8  each have a rear transition portion  14  inclined toward the base surface  16  relative to the support surfaces  9 . 
     The rear edges  11  delimiting the rear transition portions  14  against the thread running direction F are rounded, as are the side edges  15  in the transition region between the lateral transition portion  18  and the side surface  12 , the secondary edge  19  in the transition region between the lateral transition portion  18  and the front transition portion  17 , and the front edge  10  in the transition region between the support surface  9  and the end face  13 . The mutually adjacent inner edges  20  of the wall portions  7 ,  8  in the region of the thread insertion slot  2  are likewise rounded. 
     The thread-guiding element  3  produced from a ceramic material is connected to the base carrier  4 , which for fastening to the traversing rod  21 , has a fastening opening  6  for receiving suitable fastening means. 
     
       
         
           
               
             
               
                   
               
               
                 List of reference signs 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
            
               
                 1 
                 Traversing thread guide 
               
               
                 2 
                 Thread insertion slot 
               
               
                 3 
                 Thread-guiding element 
               
               
                 4 
                 Base carrier 
               
               
                 5 
                 Thread-guiding channel 
               
               
                 6 
                 Fastening opening 
               
               
                 7 
                 Wall portion 
               
               
                 8 
                 Wall portion 
               
               
                 9 
                 Support surface 
               
               
                 10 
                 Front edge 
               
               
                 11 
                 Rear edge 
               
               
                 12 
                 Side surface 
               
               
                 13 
                 End face 
               
               
                 14 
                 Rear transition portion 
               
               
                 15 
                 Side edge 
               
               
                 16 
                 Base surface 
               
               
                 17 
                 Front transition portion 
               
               
                 18 
                 Lateral transition portion 
               
               
                 19 
                 Secondary edge 
               
               
                 20 
                 Inner edge 
               
               
                 21 
                 Traversing rod 
               
               
                 22 
                 Cross-wound package 
               
               
                 23 
                 Package drive roller 
               
               
                 24 
                 Thread 
               
               
                 F 
                 Thread running direction