WORKPLACE OF AN AIR SPINNING MACHINE

Description

[0001] The invention relates to a workstation of an air spinning machine with an air-spinning device for spinning a thread from a supplied fiber sliver and a thread guide unit downstream of the air-spinning device with an inlet opening for receiving the thread emerging from the outlet opening of the air-spinning device and a thread guide channel for passing at least the air-spun thread coming from the air-spinning device.

[0002] In the textile industry, various processes and spinning devices are known for the production of textile threads. Ring spinning machines and / or open-end rotor spinning machines, for example, have long been widely used and have proven extremely effective. Furthermore, so-called air-jet spinning machines are also known, particularly in connection with the processing of synthetic yarn materials.

[0003] For example, WO 2019 / 012143 discloses an air-jet spinning machine with an air-jet spinning device that forms a thread from a fiber sliver via an air flow circulating a hollow spinning cone. The fiber sliver, previously drawn by a drafting system upstream of the air-jet spinning device, is fed to the air-jet spinning device via a fiber sliver inlet of the air-jet spinning device and enters a vortex chamber surrounding a hollow spinning cone, which can be subjected to a vortex air flow by means of a nozzle device.The jet device generates an air stream circulating the spinning cone, whereby the free fiber ends of the fiber sliver are placed around the spinning cone in a known manner and wound helically around core fibers. This produces a thread with suitable strength properties. This thread is transported via an outlet opening of the air-jet spinning device to a winding device, by means of which the spun thread is wound onto a winding package in a defined manner. After leaving the air-jet spinning device, the thread passes through a thread deflection unit and a thread guide channel adjacent to the thread deflection unit.

[0004] If the spinning process in an air-jet spinning device is interrupted, for example, due to a break in the supplied fiber sliver or because the spun thread was otherwise separated by a controlled cut of a thread cleaner, the subsequent piecing process, which serves to remedy the spinning interruption, must first retrieve the thread end of the already spun thread, which is usually wound onto a corresponding winding package, and transport it through the air-jet spinning device into the area of ​​the drafting system or the spinning cone within the vortex chamber in the thread take-off direction. An air flow initiated by a blowing pulse is usually used as the transport medium for bringing the thread end close to an outlet opening of the air-jet spinning device.As soon as the thread end is presented to the outlet opening, it is sucked into the air spinning device by a suction air flow directed opposite to the thread take-off direction usual during the spinning process and transported to the vortex chamber.

[0005] In the known air-jet spinning machines with a thread guide unit having a thread guide channel arranged downstream of the air-jet spinning device in the thread take-off direction, an unreliable return of the thread taken up from the winding package occurs due to a thread-guide-free area between the inlet opening of the thread guide unit and the outlet opening of the air-jet spinning device opposite it, so that the thread cannot be reliably introduced into the air-jet spinning device in order to carry out piecing.

[0006] Based on this, the invention is based on the object of providing a work station of an air spinning machine which enables reliable piecing.

[0007] The invention solves the problem by a workstation of an air spinning machine having the features of claim 1. Advantageous developments of the thread guide element are specified in the dependent claims 2 to 6.

[0008] The thread guide element according to the invention has a channel body having a through-channel for arrangement between the outlet opening of the air-jet spinning device and the inlet opening of the thread guide unit, which has a thread guide channel for conducting a thread running between the air-jet spinning device and the winding device. The channel body in turn has a connecting section which can be connected to the air-jet spinning device and by means of which the channel body can be positioned with its first open end of the through-channel in the region of the outlet opening of the air-jet spinning device. In addition, the channel body has an end section which can be arranged opposite the inlet opening and which ensures reliable entry of the thread from the inlet opening into the through-channel orto receive a thread emerging from the inlet opening, is adapted to a contour of the thread guide unit surrounding the inlet opening. The end section is accordingly designed in such a way that a reliable transition of a thread emerging from the inlet opening into the through-channel of the channel body can be ensured. The distance between the end section of the through-channel or a second open end of the through-channel delimited by the end section and the inlet opening is selected in such a way that a thread end emerging from the inlet opening is not deflected in the direction of the gap formed between the end section or the second open end and the inlet opening in such a way that the thread end is guided through the gap.Further preferably, the end section is designed to position the open second end opposite the inlet opening without forming a gap between the end section and the contour surrounding the inlet opening that allows the thread end to pass through. For this purpose, the end section can, for example, have a different shape or size than the rest of the channel body.

[0009] The thread guide element according to the invention ensures a reliable transition of the thread end to be returned to the air-jet spinning device for piecing. Due to its design adapted to the inlet opening of the thread guide unit, the end section ensures reliable reception of the thread end upon exiting the inlet opening of the thread guide unit. The thread located in the through-channel of the channel body of the thread guide element is reliably guided along the through-channel via the first open end of the through-channel into the outlet opening of the air-jet spinning device, from where the thread end reaches the position required for piecing with the fiber sliver.

[0010] The thread guide element according to the invention thus ensures the reliable return of a thread end, usually taken up from a winding bobbin, into the spinning device in order to achieve reliable piecing with the supplied fiber sliver. The thread guide element thus bridges the typically thread-guide-free intermediate section between the thread guide unit and the outlet opening of the spinning device, thus preventing malfunctions due to faulty thread return. The thread guide element according to the invention reliably ensures cost-effective and simple thread return into the spinning device and thus guarantees piecing reliability.

[0011] The arrangement of the thread guide element on the spinning device can, in principle, be carried out in any desired manner. For example, suitable fastening screws or clamping means can be provided for this purpose, by means of which the thread guide element can be releasably arranged in the area of ​​the outlet opening of the spinning device. According to a particularly advantageous embodiment of the invention, however, the connecting section of the channel body of the thread guide element is designed for a bayonet-type connection to the spinning device.

[0012] According to this embodiment of the invention, the connecting section in the region of the first open end or the spinning device in the region of the outlet opening has a longitudinal slot, at the end of which a short transverse slot is connected at an angle, which can be brought into operative connection with a corresponding engagement element on the other of the spinning device or connecting section. The design of the connection between the connecting section and the spinning device via a bayonet-type connection enables a particularly simple and reliable arrangement of the thread guide element on the spinning device and, if necessary, the disassembly of the thread guide element from the spinning device in the event of maintenance work.

[0013] The channel body can, in principle, be made of any material, e.g., from suitable metallic materials. However, according to a particularly advantageous embodiment of the invention, the channel body is formed from a plastic material, in particular PVC. The use of a plastic material enables particularly simple and cost-effective production of the thread guide element. Furthermore, the use of a plastic material allows for simple shaping of the end section of the channel body, which can be arranged in the region of the inlet opening and through which the thread exiting the inlet opening and being returned to the spinning device is received in the thread guide element.

[0014] There are fundamentally diverse possibilities for adapting the end section to the contour of the thread guide unit surrounding the inlet opening. According to a preferred embodiment, the thread guide unit has a thread deflection unit for the defined deflection of the thread, wherein the thread deflection unit forms the inlet opening. At its end facing away from the inlet opening, the thread deflection unit has an outlet which is coupled to the inlet opening via an intermediate thread deflection section and via which the thread deflection unit can be connected to the thread guide channel for guiding the thread through the thread guide unit to the inlet opening. Such a thread guide unit equipped with a thread deflection unit enables the deflection of the thread in a thread path arranged between the spinning device and the winding device, whereby a work station of the air-jet spinning machine along the thread path can be designed more compactly.The thread deflection unit is preferably designed to deflect the thread at an angle of less than 90° between the passage axes of the inlet opening and the outlet. Particularly preferably, the thread deflection unit comprises a thread deflection roller with a thread guide notch along which the thread can be guided in a deflected manner. The thread guide notch can have a cross-sectional shape as required, for example, a U-, V-, C-, W-, or similar shape.

[0015] According to an advantageous embodiment, the end section is funnel-shaped. This design of the end section, when positioned opposite the inlet opening, ensures particularly reliable reception of the thread to be returned in the thread guide element and thus reliable feeding of the thread end into the spinning device for carrying out the piecing process.

[0016] According to a further embodiment of the invention, the end section is adapted to the contour of the thread deflection unit in the region of the inlet opening, in particular to the contour of the thread deflection roller of the thread deflection unit. According to this embodiment of the invention, the thread guide element extends with its connecting section directly up to the thread deflection roller provided for thread deflection. Adapting the contour of the end section to the thread deflection roller enables the end section to be arranged particularly close to the inlet opening, thus ensuring particularly reliable reception of the thread to be fed back and, moreover, permitting particularly simple and cost-effective production of the thread guide element, wherein the end section is provided, for example, in a scoop-shaped manner with a cross-section adapted to the radius of the thread deflection roller.

[0017] Furthermore, according to a preferred embodiment, the channel body has a plurality of air passages along the passage channel for effecting a rotational flow within the passage channel as the thread is passed through. The air passages are preferably arranged circumferentially, in particular spirally, around the channel body. The air passage can furthermore preferably have an opening axis tangential to the passage channel, which more preferably points obliquely to the thread passage axis running through the passage channel and the thread running direction. This allows the generation of a less turbulent rotational flow within the passage channel. Such a rotational flow within the passage channel has an advantageous effect as the thread is passed through, particularly during the air spinning process, in that protruding edge fibers of the thread wrap around the thread and adhere to the thread or are accordingly integrated.This allows the hairiness of the thread passing through to be influenced in such a way that this yarn parameter can be reduced in magnitude, thereby increasing the strength of the thread. Exposing the thread to the rotating flow is particularly beneficial for reducing hairiness in long-staple fibers.

[0018] The rotational flow can be generated passively or actively. For the purposes of the present invention, passive generation refers to a rotational flow generated purely by the thread passing through the passageway at high speed. This high speed causes air to be entrained and thus sucked from the air passages into the passageway, ultimately resulting in a rotational flow.

[0019] The thread is passed through in the direction of thread travel, i.e. either in the direction of the spinning device during a piecing process or in a direction opposite thereto during regular spinning operation, preferably supported by negative or positive pressure. For this purpose, the thread can be passed through the passage channel accompanied by compressed air or suction air. The compressed air or suction air can preferably be generated externally of the thread deflection unit, for example in the air spinning device, or internally, in particular via a compressed air connection on the thread deflection unit for introducing compressed air into the thread deflection unit in the direction of the inlet opening. Alternatively or additionally, the compressed air can be supplied via a compressed air duct that supplies the air outlets with compressed air and is connected to a compressed air source.The compressed air duct can, for example, extend in a ring-like manner around the duct body, coupled to the respective air outlets.

[0020] The inventive workstation of an air-jet spinning machine ensures, through the use of the inventive or further developed thread guide element described above, reliable thread guidance of the thread end emerging from the thread guide unit, in particular from the thread deflection unit, and returning it to the air-jet spinning device. The thread emerging from the thread guide unit, in particular from the thread deflection unit, is reliably received in the through-channel of the thread guide element and fed via the through-channel to the air-jet spinning device. Malfunctions at the workstation of the air-jet spinning machine due to an incorrectly returned thread end can be reliably avoided by using the thread guide element, thus further increasing the operational reliability of the workstation of the air-jet spinning machine.

[0021] An embodiment of the invention is explained below with reference to the drawings. In the drawings: Fig. 1 shows a thread guide unit with a thread deflection unit in conjunction with a thread preparation device arranged on a thread guide channel and an air spinning device; Fig. 2 shows a schematic representation of a thread guide element arranged between the air spinning device and the thread deflection unit; Fig. 2a shows a front view of the thread guide element of Figure 2 and Fig. 3 shows a further embodiment of a thread guide element.

[0022] Figure 1shows a schematic representation of a thread guide unit with a thread deflection unit 2 arranged downstream of an air-jet spinning device 6 along a thread path, which is connected to a thread preparation device 5 via a thread guide channel 4 connected to its output 3. The air-jet spinning device 6, the thread guide unit with the thread deflection unit 2 and the thread guide channel 4, as well as the thread preparation device 5, are components of a work station (not shown here) of an air-jet spinning machine, in which a thread 27 emerging from the air-jet spinning device 6 is wound onto a take-up package (not shown here) during the spinning process.

[0023] During the normal air-jet spinning process, a stored fiber sliver on its way to the take-up package first passes through a drafting system upstream of the air-jet spinning device 6 in the fiber sliver running direction R, where it is drafted in a defined manner. Via a pair of output rollers of the drafting system (not shown here), the drafted fiber sliver is then fed to the air-jet spinning device 6, within which the fiber sliver is formed into a thread 27 in the region of a spinning cone (not shown here) under the influence of a rotational flow generated by an air stream emerging from a nozzle block, wherein edge fibers of the fiber sliver are looped helically around its core fibers.

[0024] The air-spun thread 27 produced in this way is drawn off from the air-spinning device 6 and drawn off via the thread guide unit with the thread deflection unit 2 and the thread guide channel 4 and through the thread preparation device 5 and then wound onto a take-up bobbin.

[0025] If spinning is interrupted during the air-jet spinning process, e.g., due to a break in the thread (27) or due to a controlled cut or uncontrolled separation of an already spun thread, a piecing process must first be performed before restarting the spinning process. To perform a piecing process, the end of the already finished thread (27), usually located on the winding package, must be provided in the area of ​​the fiber sliver of the air-jet spinning device 6.

[0026] For this purpose, the thread end of the already produced thread (27) is usually retrieved from the winding package or a defined thread end position via a thread end carrying unit, such as a suction nozzle, and transferred to a thread preparation device 5 equipped with a holding and opening tube 7, arranged downstream of the air spinning device 6 in the fiber sliver running direction R, as shown in Figure 1 is shown. In the holding and dissolving tube 7, the thread end is largely freed of twists and loose fibers.

[0027] For this purpose, the yarn preparation device 5 has a holding and opening tube 7 arranged in a receiving housing 8. The receiving housing 8, in turn, has an annular space 9, to which a compressed air source 11 is connected via a pneumatic line 10. A valve 12 is connected to the pneumatic line 10, which is connected via a control line 13 to a control device of the spinning station (not shown here). The holding and opening tube 7 is equipped with at least one blow nozzle 14, which is connected to the annular space 9.

[0028] As is known per se, a thread 27 must first be inserted into the holding and opening tube 7 in order to prepare its thread end for a thread joining process in the air spinning device 6. For this purpose, the retrieved thread end is provided at the thread preparation device 5 so that it can be pneumatically threaded into the holding and opening tube 7. The thread preparation device 5 can, as in Figure 1 shown, cooperate with at least one cutting device 15, which cuts the retrieved thread 27 to length as required. During the cutting process, the valve 12 is activated and blown into the holding and opening tube 7 via the blow nozzle 14 in order to thread or suck in the cut thread end into the holding and opening tube 7. The threaded thread end is freed of yarn twists and loose fibers in the holding and opening tube 7.

[0029] How Figure 1As can also be seen, the thread preparation device 5 is coupled to a thread guide channel 4 for guiding the thread 27, wherein the thread guide channel 4 is arranged in the fiber sliver running direction R between the thread deflection unit 2 and the thread preparation device 5. The fiber sliver running direction R is identical to the running direction of the thread 27 in the spinning operation of the air-jet spinning machine, in which the thread 27 is spun by means of the air-jet spinning device 6.

[0030] The thread guide channel 4 is connected to an outlet 3 of the thread deflection unit 2, which has a thread deflection roller 16 for the controlled deflection of the thread 27, by means of which the thread 27 is deflected during the return of the thread end in the direction of the air-jet spinning device 6. The thread deflection unit 2 further comprises a receptacle for a compressed air connection 17, via which compressed air can be supplied via an inlet 18 into the channel section 19 pointing in the direction of the air-jet spinning device 6, whereby a suction effect is simultaneously created in the thread guide channel 4.

[0031] Adjacent to the inlet opening 20 of the thread deflection unit 2 is an end section 21 of a thread guide element 1, the end section 21 having a scoop-shaped contour adapted to the contour of the thread deflection roller 16. A through-channel 22 extends on the thread guide element 1 from the end section 21 to a connecting section 23 as far as an outlet opening 24 of the air-jet spinning device 6. For the arrangement of the thread guide element 1, a connecting plate 25 is arranged on the channel body 26, which can be connected to the air-jet spinning device 6 via a bayonet connection (not shown here). Due to the existing air flow, the returned thread 27 is reliably guided via the through-channel 22 through the funnel-shaped outlet opening 24 into the air-jet spinning device 6.The thread guide element 1 thus bridges the area between the inlet opening 20 of the thread deflection unit 2 and the air spinning device 6 and ensures reliable thread guidance.

[0032] An alternative embodiment to the one in the Figures 1 and 2 and 2a shown thread guide element 1 is in Figure 3 The thread guide element 1a shown there has, in contrast to the one shown in the Figures 1 , 2 and 2a The thread guide element 1 shown has a funnel-shaped end section 21a, which ensures reliable reception of the returned thread end. List of reference symbols

[0033] 1, 1a Thread guide element 2 Thread deflection unit 3 Output 4 Thread guide channel 5 Thread preparation device 6 Spinning device / air spinning device 7 Holding and opening tube 8 Housing 9 Annular space 10 Pneumatic line 11 Compressed air source 12 Valve 13 Control line 14 Blow nozzle 15 Cutting device 16 Thread deflection roller 17 Compressed air connection 18 Inlet 19 Channel section 20 Inlet opening 21, 21a End section 22 Through channel 23 Connection section 24 Outlet opening 25 Connecting plate 26 Channel body 27 Thread R Fiber ribbon running direction

Claims

1. Workstation of an air-spinning machine, comprising - an air-spinning device (6) for spinning a thread (27) from a supplied sliver and - a thread-guiding unit, which is downstream of the air-spinning device (6) and has an inlet opening (20) for receiving the thread (27) exiting from the outlet opening (24) of the air-spinning device (6) and a thread guide channel (4) for conducting at least the air-spun thread (27) coming from the air-spinning device (6), wherein the thread-guiding unit comprises a thread deflection unit (2) for defined deflection of the thread, the thread deflection unit (2) forms the inlet opening (20) and comprises an exit (3) at its end facing away from the inlet opening (20), which is coupled to the inlet opening (20) via an interposed thread deflection section and via which the thread deflection unit (2) can be connected to the thread guide channel (4) for guiding the thread (27) through the thread-guiding unit to the inlet opening (20), characterised in that a thread-guiding element (1, 1a) is arranged in the area between the outlet opening (24) of the air-spinning device (6) and the inlet opening (20) of the thread-guiding unit, wherein the thread-guiding element (1, 1a) comprises a channel body (26) having a through-channel (22), which comprises - a connection section (23) configured for connection to the spinning device (6) for arranging a first open end of the through-channel (22) in the region of the outlet opening (24) of the spinning device (6) and - an end section (21, 21a) which can be arranged facing the inlet opening (20), wherein the end section (21, 21a), in order to receive a thread (27) exiting from the inlet opening (20), is matched to a contour of the thread-guiding unit surrounding the inlet opening.

2. Workstation according to claim 1, characterised in that the end section (21) is matched to the contour of the thread deflection unit (2) in the area of the inlet opening (20), more particularly to the contour of a deflection roller (16) of the thread deflection unit (2).

3. Workstation according to claim 1 or 2, characterised in that the connection section (23) is designed for bayonet-coupling-type connection to the spinning device (6).

4. Workstation according to one or more of the preceding claims, characterised in that the channel body (26) is made of a plastic material, more particularly PVC.

5. Workstation according to one or more of the preceding claims, characterised in that the end section (21, 21a) is funnel-shaped.

6. Workstation according to one or more of the preceding claims, characterised in that the channel body (26) has a plurality of air passages along the through-channel (22), for causing a rotational flow within the through-channel (22).