THREAD-SPLICING DEVICE FOR A WORKSTATION OF A TEXTILE MACHINE PRODUCING CROSS-WOUND BOBBINS

Abstract

A thread-splicing device for a workstation of a textile machine that produces cross-wound bobbins and has a splicing prism with a splicing channel to which pneumatic pressure can be applied, as well as thread-guiding plates arranged on both sides of the splicing channel, and which is equipped with thread-locking means. At least one interfering element is positioned on both sides of the splicing prism in a region between the thread-guiding plates and a thread-locking means in such a way that the thread ends to be spliced contact the interfering element during the splicing process.

Claims

1. A thread-splicing device for a workstation of a textile machine that produces cross-wound bobbins, the thread-splicing device comprising: a splicing prism with a splicing channel to which pneumatic pressure can be applied; thread-guiding plates arranged on both sides of the splicing channel and which is equipped with thread-locking means; and at least one interference element positioned on both sides of the splicing prism in a region between the thread-guiding plates and the thread-locking means in such a way that thread ends to be spliced contact the at least one interference element during splicing process.

2. The thread splicing device according to claim 1, wherein the at least one interference element is always arranged on a larger of the thread-guiding plates.

3. The thread splicing device according to claim 1, wherein the at least one interference element is designed and arranged such that a thread contact surface of the at least one interference element runs at a right angle to a side wall of the splicing prism.

4. The thread splicing device according to claim 1, wherein the at least one interference element has a wall element that is equipped with a thread contact surface and is arranged at an angle with respect to a side wall of the splicing prism.

5. The thread splicing device according to claim 1, wherein the at least one interference element has multiple wall elements each equipped with a thread contact surface.

6. The thread splicing device according to claim 1, wherein the at least one interference element is made of an abrasion-resistant material.

7. The thread splicing device according to claim 6, wherein the at least one interference element is made of a ceramic material.

8. The thread splicing device according to claim 6, wherein the at least one interference element is made of a high-strength metallic material.

9. The thread splicing device according to claim 1, wherein the at least one interference element is replaceably fastened to the splicing prism.

10. The thread splicing device according to claim 9, wherein the at least one interference element is fastened to the splicing prism by a screw connection.

11. The thread splicing device according to claim 1, wherein the at least one interference element is fastened to the splicing prism by an adhesive connection.

12. The thread splicing device according to claim 3, wherein the thread contact surface of the at least one interference element runs straight in a region of contact of the thread ends.

13. The thread splicing device according to claim 3, wherein the thread contact surface of the at least one interference element has a bulge in a region of contact of the thread ends.

14. The thread splicing device according to claim 1, wherein the thread splicing device, apart from a splicing prism equipped with the at least one interference element, has additional devices equipped with the thread-locking means, an attachment plate equipped with the thread-locking means or a thread brake element.

Description

[0037] FIG. 1 shows a side view of a workstation of a cross-winding machine with a thread splicing device designed according to the invention,

[0038] FIG. 2 shows a thread splicing device, the splicing prism of which is equipped with an interfering element according to the invention, during the insertion of the thread ends to be connected, in plan view,

[0039] FIG. 3 shows the thread splicing device according to FIG. 2 during the splicing process,

[0040] FIG. 4 shows a thread splicing device according to the prior art during the splicing process,

[0041] FIG. 5 shows a first embodiment of an interfering element according to the invention, with a recess in the region of the thread contact surface,

[0042] FIG. 6 shows a second embodiment of an interfering element according to the invention having a straight thread contact surface,

[0043] FIG. 7 shows a third embodiment of an interfering element according to the invention with a wall part that is arranged at an angle with respect to the side wall of the splicing prism and has a thread contact surface,

[0044] FIG. 8 shows another embodiment of an interfering element according to the invention with multiple wall parts, each having a thread contact surface.

[0045] FIG. 1 schematically shows a cross-wound bobbin producing textile machine, in the embodiment a so-called cross-winding machine 1. Cross-winding machines 1 of this kind usually have a plurality of identical workstations 2 arranged in series next to one another, in the present case so-called winding stations, on which, as known and therefore not explained in more detail, spinning cops 9 produced on a ring spinning machine, which have relatively little yarn material, are rewound into large-volume cross-wound bobbins 15. After completion thereof, these cross-wound bobbins 15 are transferred, for example, by means of an automatically operating (not shown) service unit, preferably a cross-wound bobbin changer, to a machine-length cross-wound transport device 21 and transported to a bobbin loading station or the like arranged at the machine end.

[0046] Such cross-winding machines 1 also have a logistics device in the form of a bobbin and tube transport system 3 in which the spinning cops 9 or unwound empty tubes circulate on transport plates 8. Of such a bobbin and tube transport system 3, only the cop feed line 4, the reversibly drivable storage section 5, one of the transverse transport paths 6 leading to the winding stations 2, and the tube return line 7 are shown in FIG. 1.

[0047] Furthermore, such automatic cross-winding machines 1 usually have a central control unit 18 which is connected via a machine bus 35 both to the separate workstation computers 29 of the individual workstations 2 and (not shown) to a control device of the service unit.

[0048] The spinning cops 9 supplied via the bobbin and tube transport system 3 are wound into large-volume cross-wound bobbins 15 in unwinding positions UP, which are in each case located in the region of the transverse transport paths 6 at the workstations 2.

[0049] For this purpose, the individual workstations 2 are known to have different devices which ensure proper operation of these workstations 2. These devices are, for example, a suction nozzle 12 for handling the upper thread 31, a gripper tube 25 for handling the lower thread 32, and a thread connecting device designed as a pneumatic thread splicing device 10. The suction nozzle 12 and the gripper tube 25 are each connected via suction air connections to a machine-length suction air channel 37. The suction nozzle 12 is pivotably mounted to a limited extent about a pivot axis 16 and the gripper tube 25 about a pivot axis 26.

[0050] Further devices (not shown in detail) of such workstations 2 of cross-winding machines 1 are, for example, a thread tensioner, thread clearer, paraffinizing device, thread cutting device, thread tension sensor, and lower thread sensor.

[0051] The pneumatic thread splicing device 10 is set back slightly in relation to the regular thread path during normal winding operation, i.e., the thread splicing device 10 is not touched by the running thread during normal winding operation.

[0052] Such workstations 2 furthermore have a winding device 24 for winding a cross-wound bobbin 15. The winding device 24 has, among other things, a bobbin frame 28 which is movably mounted about a pivot axis 13 and has a device for rotatably holding a cross-wound bobbin tube. In the embodiment, the cross-wound bobbin 15, which is freely rotatable in the cross-wound frame 28, rests with its surface on a driven groove drum 14 and is entrained by the latter during winding operation by means of a frictional connection. The thread to be wound onto the cross-wound bobbin 15 comes from a spinning cop 9, which is positioned in an unwinding position UP in the region of the transverse transport line 6.

[0053] FIG. 2 shows a plan view of a thread splicing device 10 having an interfering element 30 designed according to the invention during the insertion of the thread ends to be spliced. As can be seen, thread locking and cutting devices 11, 17 are arranged above and below the thread splicing device 10. That is, the thread locking and cutting device 11 above has a thread locking device 11A for fixing a so-called upper thread 31 connected to the cross-wound bobbin 15 and fed by the suction nozzle 12, as well as a thread cutting device 11B for cutting to length a so-called lower thread 32 connected to a feed spinning head 9 and fed through the gripper tube 25.

[0054] Accordingly, the thread locking and cutting device 17 below has a thread locking device 17A for fixing the lower thread 32, which is connected to the template spinning cop 9 and is fed through the gripper tube 25, as well as a thread cutting device 17B for cutting to length the upper thread 31 fed by the suction nozzle 12. For reasons of clarity and because it is not absolutely necessary for understanding the invention, a known thread feeder also arranged in the area of the thread splicing device 10 has not been shown.

[0055] As can further be seen from FIG. 2, the thread splicing device 10 has an air distribution block 33 in which so-called holding and unraveling tubes 34 are embedded. A splicing prism 19, which has a pneumatically actuatable splicing channel 20, is arranged on the air distribution block 33.

[0056] The splicing prism 19 is exchangeably fixed to the air distribution block 33, for example via a screw connection 39.

[0057] In the installed state of the splicing prism 19, blow-in openings leading into the splicing channel 20 are connected to a pneumatic bore in the air distribution block 33, which is connected to a compressed air source via a corresponding line in which, for example, a solenoid valve is connected.

[0058] As can be seen, for example, from FIGS. 2, 3 and 4, so-called thread guide plates 22, 23 are arranged in each case in the region of the outlet openings of the splicing channel 20 of the splicing prism 19, wherein the thread guide plates 22 and 23 are designed differently. That is to say, the smaller thread guide plates 22 are flat and are mounted parallel to the side walls 27 of the splicing prism 19 in the installed state. The arrangement of the small thread guide plates 22 is preferably also selected in such a way that the leading deflection edge of the thread guide plates 22 lies approximately at the height of the center of the splicing channel 20 of the splicing prism 19. The associated larger thread guide plates 23 arranged on the opposite side of the outlet openings of the splicing channel 20 each have an angle with respect to the side wall 27 of the splicing prism 19.

[0059] As shown in FIGS. 2 and 3, a so-called interfering element 30 according to the invention is also arranged on the large thread guide plates 23. These interfering elements 30 according to the invention, the function of which will be explained later on the basis of FIGS. 3 and 4, can have different embodiments and be connected to the splicing prism 19 differently. The interfering elements 30 can, for example, be connected to the splicing prism 19 by means of a screw connection 39 in a easily releasable and replaceable manner or they can be firmly connected to the splicing prism 19, for example by an adhesive.

[0060] FIGS. 5 to 8 show some of the possible embodiments of a interfering element 30 according to the invention.

[0061] FIGS. 5 and 6 show, for example, interfering elements 30 according to the invention, with a wall part 41 arranged parallel to the side wall of the splicing prism 19, but with differently designed thread contact surfaces 36. The interfering element 30 according to FIG. 6, for example, has a substantially straight continuous thread contact surface 36, while the interfering element 30 shown in FIG. 5 is provided with a bulge 38 in the region of its thread contact surface 36. Such a bulge 38 yields an advantageous centering of the thread ends to be spliced during the splicing process.

[0062] The interfering element 30 shown in FIG. 7 has a wall part 41 equipped with a thread contact surface 36, which is arranged at an angle with respect to the associated side wall 27 of the splicing prism 19 when the interfering element 30 is in an installed state.

[0063] The interfering element 30 shown in FIG. 8 has two wall parts 41 which are each equipped with a thread contact surface 36. When the interfering element 30 is in the installed state, the first wall part 41 is arranged parallel with respect to the associated side wall 27 of the splicing prism 19, while the second wall part 41 is positioned at an angle with respect to the side wall 27 of the splicing prism 19.

[0064] The above-described interfering elements 30 also have, for example, a fastening hole 40 and can therefore be easily attached to the splicing prism 19 by means of a screw connection, which can be easily detached if necessary.

[0065] The invention is expressly not intended to be limited to the embodiments described above for interfering elements 30. The interfering elements 30 can, for example, also have more than two wall parts 41 equipped with thread contact surfaces 36. It is also conceivable that the wall parts 41 are formed only partially with a thread contact surface 36 and are at least partially hollow. This means that wall part 41 has, for example, a narrow edge designed as a thread contact surface 36, while the wall part 41 is hollow in the region of the thread contact surface 36. Furthermore, the design of the thread contact surface 36 could also have a different, for example, wavy shape.

[0066] Function of the thread splicing device designed according to the invention:

[0067] In the case of a interruption of winding, for example due to a regular clearer cut or a thread breakage above the thread tensioner, the lower thread 32 remains held in the thread tensioner of the workstation 2 since the thread clearer has triggered the thread clamping function of the thread tensioner due to the absence of a dynamic thread signal. The lower thread 32 held in the thread tensioner is then removed by the gripper tube 25, which is initially pivoted into the region of the thread tensioner for this purpose and sucks in the lower thread 32 there. The thread tensioner simultaneously releases the lower thread 32.

[0068] When the successful pick-up of the lower thread 32 is registered, for example by a sensor arranged inside the gripper tube 25 (not shown), the gripper tube 25 swivels into an upper position as indicated in FIG. 2. The lower thread 32 is thereby inserted into the splicing channel 20 of the splicing prism 19 and into the thread locking element 17A of the lower, and the thread cutting element 11B of the upper or lower thread locking and thread cutting device 11, 17.

[0069] Approximately simultaneously, the upper thread 31 that has run onto the cross-wound bobbin 15 is picked up by the suction nozzle 12 and also inserted into the splicing channel 20 of the thread splicing device 10. The suction nozzle 12 threads the upper thread 31, as shown in FIG. 2, into the splicing channel 20 of the splicing prism 19, into the thread locking element 11A of the upper thread locking and cutting device 11, and into the thread cutting element 17B of the lower thread locking and cutting device 17. Subsequently, the thread cutting devices 11B and 17B are activated, and the lower and upper threads 31 and 32 are cut to a predetermined length. The cut, free thread ends of the upper and lower threads 31, 32 are disposed of by the gripper tube 25 or the suction nozzle 12.

[0070] The thread ends of the upper thread 31 and the lower thread 32 projecting out of the splicing channel 20 of the splicing prism 19 are each sucked into one of the vacuum-pressurizable holding and unraveling tubes 34, and are at least partially freed there from their thread twist, preferably pneumatically.

[0071] Subsequently, the prepared thread ends of the upper thread 31 and lower thread 32 are pulled back into the splicing channel 20 by a so-called thread feeder (not shown) so that the thread ends are positioned next to each other in the splicing channel 20 with a predetermined overlap, i.e., the thread ends of the upper and lower threads 31, 32 are positioned so that they each protrude slightly from the splicing channel 20. By correspondingly controlling, for example, an electromagnetic valve, splicing air is subsequently blown into the splicing channel 20 of the splicing prism 19 via blow-in openings, and the fibers of the thread ends of the upper thread 31 and lower thread 32 located in the splicing channel 20 are entangled with each other.

[0072] During this splicing process, as indicated in FIG. 4 on the basis of the prior art, splicing air with a helical alignment also escapes from the splicing channel 20 via the outlet openings of the splicing channel 20, with the result that, if no special measures are employed, relatively uncontrolled yarn movements occur in the free space between the thread guide plates 22, 23 and the thread locking elements 11A or 17A.

[0073] In particular in the case of coarse yarns, such uncontrolled thread movements have a very negative effect on the thread splice to be created, that is to say, coarse yarns can often hardly be spliced properly with the well-known thread splicing devices 10 shown in FIG. 4.

[0074] In order to be able to ensure the creation of proper thread splices even with coarse yarns, the thread splicing devices 10 are modified with interfering elements 30 according to the invention.

[0075] That is to say, an interfering element 30, which has at least one wall part 41 with a thread contact surface 36 is attached to the larger of the two yarn guide plates 23 arranged on the output side of the splicing channel 20 of the splice prism 19.

[0076] As shown in FIG. 3, the thread contact surface 36 of the interfering elements 30 projects into the free space between the thread guide plates 22, 23 and the thread locking elements 11A or 17A in such a way that the thread ends to be spliced rest against the thread contact surfaces 36 of the interfering elements 30 during the splicing process.

[0077] This contact of the thread ends on the interfering elements 30 yields a considerable calming of the thread ends, with the result that almost yarn-like yarn connections are created even when processing coarse yarns.

TABLE-US-00001 List of reference signs 1 Cross-winding machine 2 Workstations 3 Bobbin and tube transport system 4 Cop feed line 5 Storage section 6 Transverse transport section 7 Sleeve return section 8 Transport plate 9 Spinning cop 10 Thread splicing device 11 Thread locking and thread cutting device 12 Suction nozzle 13 Pivot axis of 28 14 Groove drum 15 Cross-wound bobbin 16 Pivot axis of 12 17 Thread locking and thread cutting device 18 Central control unit 19 Splicing prism 20 Splicing channel 21 Cross-wound transport device 22 Thread guide plate 23 Thread guide plate 24 Winding device 25 Gripper tube 26 Pivot axis of 25 27 Side wall of 19 28 Bobbin frame 29 Workstation computer 30 Interfering element 31 Upper thread 32 Lower thread 33 Air distribution block 34 Holding and unraveling 35 Machine bus 36 Thread contact surface 37 Suction air channel 38 Bulge 39 Screw connection 40 Fastening hole 41 Wall part UP Unwinding position