EP0691300A1 - Yarn connecting device for textile machines making cross-wound packages - Google Patents

Abstract

A yarn connecting appts. for a textile machine producing crossover spools has, outside the normal yarn run, a splicing device (22) for pneumatically connecting the yarn ends, clamping and cutting devices in the splicer area, yarn advance devices supplied with suction air to position yarn ends to be spliced and means for laying ends in the splicer. Here the yarn advance is formed as a gripper tube (25) where its swivel range is set that its assigned yarn is correctly placed in its final position in the splicer (22). When the tube swivels, an attached device intersects the path of a stretched second yarn to catch and carry it also to the correct final position in the splicer. Pref. the gripper tube has at its end a spring-loaded swivelling flap (18) with the means for yarn advance, i.e. a yarn capture hook (23) jutting radially over the tube in the flap front plate (65) area. The flap has, between its axis (19) and capture hook, a thread guide (54) comprising a snout-like attachment (61) jutting over the flap in its swing direction (S) and at the snout, a thread guiding profile (54). There is a spring (53) inserted at the swivel axis (19) between flap and tube which acts so that the flap shuts and, at the tube's final, upper position, is a spring-loaded stop (33) having a flange-like support which corresponds with an engaging edge (55) on the flap. <IMAGE>

Description

The invention relates to a thread connecting device for textile machines producing cross-wound bobbins, with a splicing device arranged outside the normal thread run for the pneumatic connection of thread ends, with clamping and cutting devices arranged in the area of the splicing device, with thread-laying elements subjected to suction air for presenting the thread ends to be spliced and means for inserting the thread ends into the splicer.

Such pneumatically operating thread connecting devices, which are generally arranged stationary at the workstations of cross winding machines, are known from numerous publications, for example DE 36 37 033 A1 or DE 40 05 752 A1. The structure and function of such thread connecting devices is also described in detail in the "AUTOCONER 238" manual from Schlafhorst.

In the case of such devices, in the event of a thread break or when a supply bobbin is changed, an automatic thread connection and / or bobbin changer is activated via the winding unit computer of the winding unit concerned. That is, first a suction nozzle is placed on the surface of the package which rotates slowly against the winding direction. After the upper thread end has been gripped, the suction nozzle swivels back into its starting position, in which the suction nozzle opening is positioned below the splicing device. The thread strand extending between the take-up spool and the suction nozzle is guided into an electronic cleaner arranged above the thread connecting device, a clamping and cutting device positioned in this area and, through corresponding guide contours of thread guide plates and thread guide brackets, drawn into the scissor halves of a cutting device located below the splicing device. During this laying, the upper thread also slides over the back of a thread catch hook positioned above the splicing device and thereby reaches the area of an open upper thread clamp.

Almost simultaneously with the suction nozzle, a looper tube positioned in a lower starting position swivels into an upper working position and thereby brings along a lower thread, previously held in a thread tensioner, and pulled off the payout spool. When the hook tube is swiveled into its upper working position, the lower thread, which is also guided on corresponding thread guide contours, slides into an open lower thread clamp, an open upper cutting device and a fork-shaped recess in the thread catch hook.

The swiveling thread catch hook places the upper and lower thread on the bottom of the prism of the pneumatic splicer. The upper thread is also pulled into the upper thread clamp. The thread ends fixed in the upper or lower thread clamp are cut to the correct length in the associated cutting devices and prepared in so-called opening tubes for the subsequent splicing. The prepared thread ends are fed into the splice channel of the prism by special thread pullers and the parallel thread ends are swirled pneumatically.

While the winding unit starts up again, the thread catch hook swivels back to its starting position in a defined manner and slowly releases the spliced thread.

The devices described above have proven themselves in practice, that is, very good splice connections can be produced with such devices. A disadvantage of these However, facilities are their relatively complex construction.

Starting from thread connecting devices of the type described above, the invention is based on the object of further improving such devices.

This object is achieved according to the invention by a device as is the subject of claim 1.

Advantageous embodiments of the invention are described in the subclaims.

The inventive design of the hook tube and its special arrangement in the thread path has the advantage that when the hook tube is pivoted into its upper working position, that is, when the lower thread is placed, via a driving means, preferably in the form of a thread laying hook, the upper thread is also carried along and in the Splicing device or the associated thread processing devices is positioned. The use of a special thread catch hook and the associated control and drive device can be dispensed with.

In a further embodiment, the hook tube has a pivotally mounted, spring-loaded hook tube flap which is arranged at the end and is equipped with a thread-laying hook. Due to the swivel-mounted, spring-loaded gripper tube flap, which closes the mouth area of the gripper tube, the air slide orifice in the suction port of the gripper tube, which was previously common with open gripper tubes, and the actuation mechanism required to control the aperture can be dispensed with.

In an advantageous embodiment, the hook tube flap has on its front side a thread-laying hook projecting axially beyond the hook tube, which crosses the path of the upper thread when the hook tube is pivoted from its initial position referred to as the zero position into a working position located above the splicing device and thereby takes the upper thread safely and gently.

In a further embodiment of the invention, the hook tube flap has a thread guide device arranged between the pivot axis and the thread laying hook. This thread guiding device essentially consists of a nose-like extension projecting beyond the gripper tube flap in the pivoting direction of the flap and a rear thread guide contour following this extension. The advantageous design of the thread guiding device ensures both safe entrainment of the lower thread laid by an auxiliary gripper in the area of the thread tensioner, the thread strand of which extends between the suction nozzle of the round magazine and the spinning cop in the unwinding position, and also a controlled separation of the threads when the hook tube enters his upper working position. The back-like increased thread guide contour also prevents the cut thread end from being accidentally caught by the suction flow in the suction nozzle of the round magazine and the suction pull in the hook tube.

In a preferred embodiment, a spring element is arranged in the region of the pivot axis of the gripper tube flap, which acts on the flap in the sense of "closing the gripper tube mouth". The spring element has a relatively soft spring characteristic, so that the gripper tube flap is kept reliably closed, but can be easily opened when starting at a stop arranged in the area of the upper working position. In this way it is ensured that the Upper thread and the lower thread in the upper working position of the hook tube are reliably separated.

The pivoting, that is to say the partial opening of the gripper tube flap, preferably takes place via a spring-loaded stop arranged in the region of the upper working position of the gripper tube. The stop has a flange-like support element against which the gripper tube flap runs with a leading edge before the gripper tube itself has reached the stop. In a preferred embodiment, the spring element of the stop has a harder spring characteristic than the spring element connected between the gripper tube flap and the gripper tube. Such a design has the advantage that when the looper tube flap starts up against the support element of the stop, the looper tube flap pivots immediately and thus both the threads are separated and the lower thread is tightened. The relatively hard spring characteristic of the stop spring element then leads to the fact that when the gripper tube starts up against the stop, all mechanical games occurring in connection with the gripper tube drive are eliminated, so that the gripper tube always moves exactly into a predetermined end position.

In a further embodiment of the invention it is provided that a stationary control link is arranged in the thread takeover position of the hook tube, into which the hook tube swivels in the event of a "normal" thread break. This stationary control link corresponds to a control cam on the hook tube flap, so that in the area of the thread takeover position the hook tube flap is pivoted away from the mouth of the hook tube and the suction opening is thus released. The suction flow present at the hook tube mouth can then grasp the lower thread held up to that point in the thread tensioner. The control cam slides when the gripper tube is pivoted back towards the upper working position from the control link, so that the spring-loaded gripper pipe flap closes again securely. The quick closing of the gripper tube flap is particularly advantageous when processing stubborn yarns, since such yarns are often difficult to fix pneumatically. However, the yarns are clamped by the closing rapier tube flap and thus held securely mechanically.

In an alternative embodiment of the invention, the thread laying hook is arranged directly on the hook tube and thereby passes through a slot-like opening in the hook tube flap. Such a design has the advantage that in the lower working position of the hook tube, that is, in the thread take-up position, the swiveling hook tube flap completely covers the thread laying hook and thereby automatically frees it of any thread loops or other adhering thread remnants. Such thread loops can form, for example, in the course of an unsuccessful splicing attempt or a thread break after the splicing process and can become attached to the thread laying hook.

Fig. 1

einen Schnitt durch eine Kreuzspulen herstellende Textilmaschine mit einer Seitenansicht einer Spulstelle,

Fig. 2

in perspektivischer Ansicht eine Fadenverbindungsvorrichtung mit einem erfindungsgemäß ausgestatteten Greiferrohr in seiner oberen Arbeitsposition,

Fig. 3

die pneumatische Spleißvorrichtung mit einem in den verschiedenen Endstellungen positionierten Greiferrohr,

Fig. 4

den Fadenlauf von Ober- und Unterfaden bei in oberer Arbeitsposition befindlichem Greiferrohr,

Fig. 5

eine Draufsicht auf den Endbereich des Greiferrohres gemäß Pfeil X der Fig. 4.

Fig. 6

eine Draufsicht auf eine alternative Ausführungsform des Greiferrohres beziehungsweise der Greiferrohrklappe,

Fig. 7

eine Vorderansicht des Endbereiches des Greiferrohres gemäß Fig. 6.

Further details of the invention can be found in an exemplary embodiment explained below with reference to the drawings. Show it:

Fig. 1

2 shows a section through a textile machine producing cross-wound bobbins with a side view of a winding unit,

Fig. 2

a perspective view of a thread connecting device with a gripper tube equipped according to the invention in its upper working position,

Fig. 3

the pneumatic splicer with a gripper tube positioned in the different end positions,

Fig. 4

the thread run of the upper and lower thread with the hook tube in the upper working position,

Fig. 5

3 shows a plan view of the end region of the gripper tube according to arrow X in FIG. 4.

Fig. 6

a plan view of an alternative embodiment of the gripper tube or the gripper tube flap,

Fig. 7

6 shows a front view of the end region of the gripper tube according to FIG. 6.

FIG. 1 shows a section through a textile machine producing cross-wound bobbins; a cross-wound bobbin winder 1 is shown in the exemplary embodiment.

As is known, such winding machines have a large number of winding units 2 arranged next to one another. Several relatively small-volume spinning bobbins are wound one after the other to form cross-wound bobbins on these winding units, which have a considerably larger yarn volume required in subsequent operations.

As shown, a cop 5, preferably produced on a ring spinning machine, is positioned on a plug-on mandrel 3 of the winding unit 2 during the rewinding process. The arbor 3 is pivotally mounted about a joint 4. The thread 6 drawn off from the payout spool 5 first passes through a take-off accelerator 7, a pre-cleaner 8 and a thread tensioner 9. The thread 6 then reaches the area of a thread connection device 10 which is somewhat set back with respect to the regular thread run and which has an upper clamping and cutting device 11 and a lower clamping and cutting device 17. The thread 6 also passes through an electronic cleaner 12 arranged above the thread connecting device 10 and a clamping and cutting device 13 assigned to the cleaner 12. The clamping and cutting device 13 is operatively connected to the cleaner 12. After passing through the cleaner 12, the thread 6 arrives at a winding device in which the thread is wound up into a cheese 15. The cheese 15 is held in a coil frame 16 and is driven by a grooved drum 14 via friction.

As further indicated in FIG. 1, the winding machine 1 has a machine-long suction channel 20 which opens into a separation chamber (not shown) on the machine end. In the separation chamber, which is connected as usual to a vacuum source, also not shown, dust and thread residues are separated.

At each winding unit 2, a suction nozzle 29 is connected via a suction air connection 21 and a gripper tube 25 is connected to the suction channel 20 via a suction air connection 24. The suction nozzle 29 is pivotally supported to a limited extent about a pivot point 31, the gripper tube 25 about a pivot point 26. The gripper tube 25 has at its free end a gripper tube flap 18, which will be explained in more detail later with reference to FIGS. 2 and 5.

The cheese winder 1 shown in FIG. 1 is a so-called round magazine machine, that is to say that in the area of each winding station 2 there is a payout bobbin changing device, denoted overall by 36. These The supply reel changer has a round magazine 37 with several, preferably six, positions for reserve heads 38. In the present exemplary embodiment, two of the reserve heads 38 standing upright in the round magazine 37 are shown, the thread ends 39 of which are held in a central suction nozzle 40 of the round magazine 37. This suction nozzle 40 is also connected to the central suction duct 20 via a suction pipe 41. As indicated in Fig. 1, the suction pipe 41 also serves as an axis of rotation and bearing 42 for the rotatably arranged round magazine 37. Below the round magazine 37, a so-called cop chute 43 can be seen, which receives the cop when the parking space of the cop concerned in the delivery position 44 rotated and an opening, not shown here, is released in the magazine bottom. With the help of the centering flaps 45, the cop is then guided onto the arbor 3 pivoted into a receiving position.

An auxiliary gripper 46 is also fastened in the area of the copslide 43 and, as indicated by an arc 47, can be pivoted in the direction of the thread tensioner 9. The auxiliary looper 46 moves the lower thread strand, which extends after changing the bobbin between the suction nozzle 40 of the round magazine and the bobbin 5 positioned on the arbor 3, into the effective area of the thread tensioner 9.

As can be seen in particular from FIGS. 2 and 5, the gripper tube 25 has a gripper tube flap 18 at the end. This gripper tube flap 18 is rotatably supported to a limited extent about a pivot axis 19. In the area of the pivot axis 19, between the gripper tube 25 and the gripper tube flap 18, a spring element 53 is activated, which acts on the gripper tube flap 18 in the sense of “closing the gripper tube mouth 27”. The hook tube flap 18 has on its front plate 65 a thread laying hook 23 projecting forward and between the thread laying hook 23 and the pivot axis 19 a thread guiding device 54. The thread guide device 54 consists essentially of a nose-like extension 61 protruding in the flap pivoting direction S and a subsequent, back-like raised thread guide contour 57.

The looper tube flap 18 also has a control cam 62 which, in conjunction with a control link 63 arranged stationary in the area of the thread take-over position III of the looper tube 25, ensures a defined opening of the looper tube flap 18.
The gripper tube flap 18 can also be opened in a defined manner in the region of the upper working position II of the gripper tube 25 via a rear leading edge 55. The leading edge 55 runs against a flange-like support element 56 of a spring-loaded stop 33 arranged in this area.

An alternative, particularly advantageous embodiment is shown in FIGS. 6 and 7.
The hook tube 25 is here directly equipped with a thread laying hook 23, that is to say the thread laying hook 23 is arranged on the hook tube 25 in a fixed or axially displaceable manner.

In this embodiment variant, too, the gripper tube 25 has a gripper tube flap 18 which is rotatably mounted to a limited extent about the pivot axis 19 and which is acted upon by a spring element 53 and normally closes the gripper tube mouth 27 with its front plate 65. The gripper tube plate 18 here, however, additionally has a slot-like opening 30 which is penetrated by the thread laying hook 23. A control cam 62 is arranged on the looper tube flap 18, as in the previously described exemplary embodiments, by means of which the looper tube flap 18 is pivoted in the direction of arrow 58 when a control link 63 arranged in the thread take-up position III starts up. The forward pivoting gripper tube flap 18 automatically frees the thread laying hook 23 from possible thread loops or the like.

Function of the facility:

If the spinning cop 5 positioned in the blow bottle 48 on a plug-on mandrel 3 has expired or if the bobbin thread is missing after a thread break, that is to say if the dynamic and static thread signal is absent from the electronic cleaner 12, the winding unit computer 64 switches on the winding unit 2 in question Cop change initiated. This means that the suction nozzle 29 is first brought into the vicinity of the surface of the cheese 15, which rotates slowly against the winding direction, and the upper thread 51 is picked up. The suction nozzle 29 then pivots into its lower working position and in doing so places the upper thread 51 in the cleaner 12, the clamping and cutting device 13 and an open clamping and cutting device 17 arranged below the splicing device 22.

This is followed by the actual changing of the cops, that is to say the empty sleeve 49 arranged on the plug-on mandrel 3 or the unwinding reel 5, which cannot be rewound without special preparation, is ejected from the blow bottle 48 and transported away via a conveyor belt 50. Subsequently, the round magazine 37 of the changing device 36 is advanced so that one of the reserve heads 38 is brought into the dispensing position 44 of the round magazine and, via an opening in the magazine bottom, the head chute 43 and the centering flap 45 reach the plug-in mandrel 3 pivoted into the receiving position. The arbor 3 then pivots back into the unwind position with the new payout spool 5. The thread end 39 of the payout spool 5 held in the central suction nozzle 40 of the round magazine 37 forms one Lower thread strand 52, which is laid by the auxiliary hook 46 in the direction of the thread tensioner 9 and held there.
At the time of changing the cop, the gripper tube 25, as indicated in FIGS. 1 and 3, is in a zero position I before the regular thread run. After the new take-up spool 5 has been replaced, the hook tube 25 swivels into the upper working position II. The hook tube mouth 27 describes a circular path 28. The hook tube flap 18 arranged in the area of the hook tube mouth 27, which is kept closed by a spring element 53, is gripped by its thread guiding device 54 the lower thread 52 and moves it in the direction of the splicing device 22. The lower thread 52 is held tight by the suction nozzle 40 in the round magazine 37. Since the circular path 28 also crosses the path of the upper thread 51, the upper thread also becomes the upper thread with the thread laying hook 23 '(embodiment FIGS. 6 and 7) arranged on the hook tube 25 or the thread laying hook 23 arranged on the hook tube flap 18 (embodiment FIGS. 2 to 5) 51 detected and also moved in the direction of the splicer 22. The upper thread 51 is held in the suction nozzle 29 parked below the splicing device 22.

The gripper tube 25 pivoted into its working position II, with its thread guide device 54 arranged on the hook tube flap 18, positions the lower thread 52 both in the clamp of the clamping and cutting device 17 arranged below the splicing device 22 and in the scissors of the clamping and Cutting device 11. At the same time, the upper thread 51 carried by the thread laying hook 23 is threaded into the upper clamping device 11. A stop 33 equipped with a spring element 34 is mounted in the area of the upper working position II of the gripper tube 25. Shortly before the gripper tube 25 with its outer surface runs against this stop 33, a leading edge 55 arranged on the gripper tube flap 18 already touches flange-like support element 56 at the stop 33. The gripper tube flap 18 is thereby pivoted somewhat about its pivot axis 19, that is to say the gripper tube flap 18 is opened somewhat. The opening hook tube flap 18 causes the two thread strands to be separated, i.e. when the hook tube flap 18 is opened, the lower thread 52 is moved somewhat away from the hook tube mouth 27 to the rear and the upper thread 51 away from the hook tube mouth to the front, which initially separates them Threads 51, 52 lying parallel in the upper clamping and cutting device 11.

The flange-like support element 56 is arranged at a certain distance behind the head of the stop in such a way that when the gripper tube 25 approaches, only the gripper tube flap 18 is initially acted upon and is pivoted somewhat in the process. Since the spring element 53, which acts on the gripper tube flap in the sense of "closing", has a softer spring characteristic than the spring element 34 of the stop 33, it is ensured that the opening dimension of the gripper tube flap 18 predetermined by the distance of the stop head / support element is reliably reached and during the start of the Gripper tube 25 on the stop 33 is not changed.

The spring-loaded stop 33 then eliminates all mechanical, drive-related play of the gripper tube 25 driven via (not shown) cam, toothed lever and pinion. This means that the hook tube 25 always moves into a precisely defined upper working position II, so that the upper thread 51 and the lower thread 52 are always inserted at the same depth and under the same wrap angle in the splicing device 22.

At the location of the stop 33, a control link (not shown) can also be arranged in the region of the upper working position II of the gripper tube 25. In this case, the gripper pipe flap 18 is in the working position II the control cam 62 is pivoted in a defined manner into a predetermined position. However, the upper thread 51 remains pulled around the thread laying hook 23.

The threads 51, 52 fixed in the upper and lower clamping and cutting devices 11, 17 are then cut. The bobbin thread residue is disposed of in the round magazine 37 via the central suction nozzle 40. The back-like design of the thread guide device 54 arranged on the hook tube flap 18 ensures that the bobbin thread residue cannot be accidentally caught by the suction flow in the mouth 27 of the hook tube 25.
The cut upper thread remainder is correspondingly disposed of by the suction nozzle 29 parked below the splicing device 22.

After the splicing process, which is known and is therefore not explained in more detail, the upper thread now connected to the lower thread still lies behind the thread laying hook 23 projecting axially beyond the hook tube flap 18. During the restart of the winding unit 2, the hook tube 25 swivels slowly in the direction of its zero position I. The thread is fed back into its regular path without curling.

The above statements essentially describe the functional sequence in the case of a cop changing circuit. A "normal" thread break results in a slightly different functional sequence.
In the event of a "normal" thread breakage, the lower thread 52 is held in the thread tensioner 9 because the thread cleaner 12 has triggered the thread clamping function of the thread tensioner 9 due to the absence of a dynamic thread signal.

While the upper thread 51, as described above, is picked up by the suction nozzle 29 on the cross-wound bobbin 15 and moved into the area of the splicing device 22, it is in the thread tensioner 9 held lower thread 52 pneumatically picked up by the hook tube 25. This means that the gripper tube 25 pivots from its zero position I backwards into the thread take-up position III located in the area of the thread tensioner 9. In the area of the thread take-up position III, a control link 63 is installed which controls the hook tube flap 18 via the control cam 62. At the same time, the thread tensioner 9 is opened so that the lower thread end 52 is sucked into the mouth region 27 of the hook tube 25. After the presence of the lower thread 52 has been detected by a sensor 32, the looper tube 25 pivots with the sucked-in lower thread 52 in the direction of its upper working position II. When the looper tube 25 is pivoted away, the control cam 62 arranged on the looper tube flap 18 slides from the control link 63, see above that the hook tube flap 18 closes under the action of the spring element 53 connected between the hook tube 25 and the hook tube flap 18 and thereby clamps the lower thread 52. Pinching the lower thread 52 between the looper tube flap 18 and the looper tube 25 is particularly advantageous when processing stubborn yarns, since purely pneumatic entrainment is often problematic with such yarns. The mechanical clamping by the hook tube flap, on the other hand, ensures that even yarns that are relatively resistant to bending are carried safely.

The further functional thread sequence of the thread break circuit essentially corresponds to the functional sequence of the cop changing circuit described at the beginning. Only the type of tightening of the lower thread 52 and the disposal of the cut lower thread remainder differ. When the gripper tube 25 enters its upper working position II, that is, when the gripper tube 25 approaches the stop 33 or a corresponding control link (not shown), the gripper tube flap 18 is pivoted somewhat in the sense of "opening". The thread, which is initially mechanically clamped, is released and released in the hook tube 25 upcoming suction train tightened. The cut bobbin thread residue is not disposed of via the suction nozzle 40 of the round magazine 37, but directly via the hook tube 25.

In the event of thread breaks following the splicing process, in particular if the thread breaks occur above the splicing device 22, it may happen that the thread end connected to the discharge cop 5 and sucked into the hook tube 25 loops around the thread laying hook 23, which leads to a malfunction in the leads winding unit concerned.

In the embodiment according to FIGS. 6 and 7, the occurrence of such disturbances is prevented by the fact that the gripper flap 25, which swivels forward in the direction of arrow 58 and which, with its slot-like opening 30, covers the thread-laying hook 23 with little play, swings the thread-adjusting hook 23 of the hook tube 25 in the thread takeover position III automatically cleans. This means that in this working position, the hook tube flap 25 runs in the control cam 62 against a control link 63 arranged in this area and frees the entire thread laying hook 23 from any thread loops when it is subsequently pivoted out.

The invention is not intended to be limited to the exemplary embodiments described, in a further embodiment of the invention it is also possible to dispense entirely with a looper tube flap and to lay the upper thread with a pin projecting laterally beyond the edge of the looper tube instead of with a thread laying hook arranged on the looper tube flap. In this case, however, the suction air flow of the gripper tube must be regulated via an air slide shutter.

Claims (13)

Thread connecting device for textile machine producing cross-wound bobbins, with a splicing device arranged outside the normal thread run for the pneumatic connection of thread ends, with clamping and cutting devices arranged in the area of the splicing device, with thread-laying elements which are subjected to suction air for placing the thread ends to be spliced and means for inserting the thread ends into the splicing device,
characterized, - That a thread-laying member designed as a gripper tube (25) is arranged in its swiveling range in such a way that a thread assigned to it is positioned functionally in an end position (II) in the splicing device (22) and - That the gripper tube (25) has a driving means that cuts the tension path of another thread when pivoting the gripper tube (25), takes the thread with it and in the end position (II) this thread is also functionally positioned in the splicing device (22). Thread connecting device according to claim 1, characterized in that - That the gripper tube (25) has a pivotally mounted, spring-loaded gripper tube flap (18) at the end and - That the driving means on the gripper tube flap (18) is arranged and formed by a thread-laying hook (23). Thread connecting device according to claim 1 and 2, characterized in that the gripper tube (25) in the axial In the direction of the thread-laying hook (23) projecting in the region of a front plate (65) of the hook tube flap (18). Thread connecting device according to Claims 1 to 3, characterized in that the hook tube flap (18) has a thread guide device (54) arranged between the pivot axis (19) and thread laying hook (23). Thread connecting device according to claim 4, characterized in that the thread guide device (54) has a nose-like projection (61) which projects beyond the hook tube flap (18) in the pivoting direction (S) and a thread guide contour (57) adjoining it. Thread connecting device according to one or more of the preceding claims, characterized in that in the region of the pivot axis (19) between the hook tube flap (18) and the hook tube (25) a spring element (53) acting on the valve in the sense of "closing the hook tube mouth" is switched on. Thread connecting device according to one or more of the preceding claims, characterized in that a spring-loaded stop (33) is arranged in the region of the upper end position (II) of the hook tube (25). Thread connecting device according to claim 6, characterized in that the stop (33) has a flange-like support element (56) which corresponds to a leading edge (55) on the hook tube flap (18). Thread connecting device according to one or more of the preceding claims, characterized in that a spring element (34) arranged in the region of the stop (33) has a harder spring characteristic than that between Gripper tube (25) and gripper tube flap (18) switched on spring element (53). Thread connecting device according to one or more of the preceding claims, characterized in that in the region of a thread take-over position (III) of the hook tube (25) a control link (63) is arranged which acts on a control cam (62) arranged on the hook tube flap (18). Thread connecting device according to claim 1, characterized in that the hook tube (25) has a thread laying hook (23) projecting beyond the hook tube mouth (27) and a cleaning device (59) is provided which sweeps over the thread laying hook (23). Thread connecting device according to claim 11, characterized in that the cleaning device (59) is part of the hook tube flap (18) which can be pivoted out about a pivot axis (19) in the direction of the arrow (58). Thread connecting device according to claims 11 and 12, characterized in that the pivotably arranged hook tube flap (18) has a slot-like opening (30) which encloses the thread laying hook (23 ') arranged stationary on the hook tube (25) with play.

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