METHOD FOR ARRANGING A FIBER SLIDER ON A SPINNING DEVICE OF A SPINNING STATION

Description

[0001] The invention relates to a method for arranging a fiber sliver on a spinning device of a spinning station, wherein the fiber sliver is fed to the spinning device for producing a spun thread from the fiber sliver by means of a drafting device having several pairs of rollers.

[0002] Spinning stations, where a pre-loaded fiber sliver is drawn by means of a drafting system and subsequently spun into a thread by a spinning device and wound onto a winding bobbin, are known in a variety of designs from the prior art. Arranged side by side, a plurality of spinning stations form a textile machine, where threads are simultaneously spun from pre-loaded fiber slivers.

[0003] Before the spinning process begins, the fiber sliver must be passed through the drafting system and the drawn fiber sliver must then be positioned in a starting position on the spinning device, where the fiber sliver can be picked up by the spinning device and spun into a thread. To pre-position the fiber sliver on the drafting system, it is currently necessary to open the drafting system, for example, by disengaging the upper rollers of the roller pairs arranged on a pendulum support from their associated lower rollers. After opening the drafting system by pivoting the pendulum support, it is possible to insert the fiber sliver into the drafting system in a predetermined manner.Subsequently, the pendulum carrier is moved back into the closed position of the drafting system, in which the latter is then started and the fiber sliver is drawn in a predetermined manner depending on the different speeds of the roller pairs for the draft ratio to be achieved.

[0004] The need to open the drafting system to arrange the fiber sliver results in longer downtimes at the individual spinning stations, which impairs the productivity of the spinning station. Furthermore, the need to open the drafting system requires a corresponding mechanical design that ensures reliable opening and closing movements.

[0005] Document JP 2009-243006 A discloses a method for arranging a fiber sliver on a spinning device of a spinning station according to the preamble of claim 1.

[0006] The document JP 2019 085662 A specifically shows how damage to a drafting system output roller and a spinning device holder can be avoided in the event of contact without going into detail about the insertion and feeding of a fiber sliver.

[0007] Document EP 1 564 317 A1 concerns the start of a piecing process in a drafting system during acceleration of a pair of rollers to an operating speed or immediately after reaching a set piecing speed. For this purpose, a fiber strand end is only fed into a clamping line of a rear pair of rollers when the transient acceleration has been completed in the speed curve of an upstream front pair of rollers and the rear pair of rollers.

[0008] Document EP 1 560 960 B1 describes a manufacturing process for a roving sliver in which the fibre strand is clamped in a pair of input rollers of the drafting system when the drafting system is started at a reduced speed.

[0009] Document US 2009 / 094958 A1, originating from the applicant, relates to a piecing process on an air-jet spinning machine in which an auxiliary thread is used, onto which fibers from a fiber sliver fed via a pair of output rollers of the drafting system are fed and wound. The auxiliary thread, which is then subjected to a take-off, is drawn off to such an extent that, after passing the auxiliary thread end, the newly spun, auxiliary-thread-free thread is separated and joined to the thread end of the thread coming from the winding package.

[0010] Based on this, the invention is based on the object of providing a method for operating a spinning station, which allows a simple and efficient arrangement of the drawn

[0011] fiber band on the spinning device.

[0012] The invention solves the problem by a method for arranging a fiber sliver on a spinning device of a spinning station with the features of claim 1. Advantageous developments of the invention are specified in the dependent claims.

[0013] Characteristic of the method according to the invention is that the roller pairs of the closed drafting system, in particular those which are individually driven, are each operated at an insertion speed which is lower than the operating speed of the drafting system in accordance with the predetermined draft ratio of the fibre sliver, the fibre sliver is then introduced into the clamping area of an input roller pair of the drafting system and the fibre sliver is then guided to the spinning device after passing through the closed drafting system and exiting the clamping area of an output roller pair of the drafting system.

[0014] According to the method according to the invention, unlike methods known from the prior art, the drafting system does not require opening, which, for example, involves lifting the upper rollers of the drafting system's roller pairs from the respective lower rollers. In the method according to the invention, the fiber sliver is introduced into the drafting system while it is closed. For this purpose, the stationary roller pairs of the closed drafting system are initially set to an insertion speed that is significantly lower than the operating speed of the roller pairs during the regular spinning process.The ability to run the roller pairs synchronously at a low speed, depending on the desired draft ratio of the sliver, particularly using individual drive technology, allows the sliver to be manually or automatically inserted into the clamping area of the feed roller pair and then guided through the drafting system in a controlled manner. Even at the lower feed speed, the sliver is drawn by the predetermined speed difference of the roller pairs according to the desired draft ratio. The preferred individual drive of each roller pair responsible for drafting allows for extremely reliable synchronization and, consequently, the achievement of a precisely adjusted draft ratio during the sliver feed toward the spinning device.Furthermore, the roller pairs are particularly preferably operable individually by means of the associated individual drives, more preferably independently of one another, such that the speed of each roller pair can be variably adjusted in the driven state if necessary, for example, to allow the draft ratio to be adjusted automatically or manually as needed at any time. According to a preferred embodiment, the respective lower rollers of a roller pair are individually driven. According to an alternative embodiment, however, the upper roller of a roller pair can also be individually driven.

[0015] After the drawn fiber sliver emerges from the clamping area of the output roller pair, it is then fed to the spinning device in such a way that it can undergo the spinning process there. Once the spinning process has resumed, the drafting system can then be operated at its operating speed again, allowing the spinning process to be carried out in a predetermined manner at the spinning station.

[0016] The method according to the invention makes it possible to dispense with a prolonged opening of the drafting system, which would interrupt the spinning process. Furthermore, the sliver emerging from the drafting system already has the drafting required for the subsequent spinning process, so that the spinning process can begin immediately with the sliver emerging from the drafting system. The option of operating the drafting system at an insertion speed below the operating speed makes it particularly possible to align the sliver precisely with the drafting system. The arrangement in the clamping area can be carried out, for example, by the operating personnel, who also monitor the guidance of the sliver through the drafting system and its arrangement on the spinning device. The low insertion speed allows very precise monitoring of the insertion process into the drafting system and its forwarding to the spinning device.

[0017] The method according to the invention can in principle be applied at any spinning station having drafting systems. For example, it is possible to carry out the method on a spinning device having a ring spinning device. According to a particularly advantageous embodiment of the invention, however, it is provided that the fiber sliver, after passing through the drafting system, is fed to a spinning device designed as an air-jet spinning device. In the air-jet spinning device of the spinning station, the outer free fiber ends are wound spirally around the core fibers to form the thread by means of a compressed air stream generated by a nozzle device. The free end of the fiber sliver lying in front of the air-jet spinning device is sucked into the air-jet spinning device by a suction air stream.

[0018] The advantageous use of the method according to the invention in conjunction with an air spinning device is thus characterized in that the spinning process can be started after passing through the drafting system without any significant delays, whereby the effectiveness of the spinning station is increased in a complementary manner.

[0019] According to a further embodiment of the method, it is provided that a suction air flow generating device for generating a suction air flow in the region of the air-jet spinning device is activated before or during the arrangement of the fiber sliver on the air-jet spinning device. According to a particularly preferred embodiment of the invention, a compressed air source, and more preferably also a vacuum source, which usually interacts with the air-jet spinning device, is activated as the suction air flow generating device before or during the arrangement of the fiber sliver on the drafting system, so that the fiber sliver subsequently fed from the drafting system to the air-jet spinning device is subjected to a suction air flow which is used to introduce the fiber sliver into the air-jet spinning device and / or to remove loose fiber material from the region of the air-jet spinning device.The suction air flow generation device reliably ensures that loose fiber material does not clog the entrance or inlet area or the spinnerets of the air-jet spinning device. The air-jet spinning process can thus be resumed in a particularly reliable and trouble-free manner.

[0020] This further development of the invention therefore takes advantage of the fact that known air-jet spinning devices usually already have corresponding suction air flow generation devices, which are activated at the appropriate time within the framework of the further developed method depending on the introduction process of the fiber sliver into the drafting system, so that any existing loose fiber material is reliably sucked away. Alternatively or additionally, other suction air flow generation devices than the one mentioned above can be provided to generate a suction air flow in the region of the air-jet spinning device. The essential factor here is that fiber residues in the region of the air-jet spinning device can be removed and / or that the fiber sliver emerging from the drafting system can be suitably fed to the air-jet spinning device.

[0021] According to a further embodiment of the invention, it is further provided that the air-spinning device is opened before or during the arrangement of the fiber sliver on the air-spinning device. Known air-spinning devices usually have at least two components. Firstly, this is a nozzle device with nozzles connected to a compressed air source via a line, wherein the air flowing out of the nozzles serves to generate the rotational flow by means of which the drawn fiber sliver is acted upon. The second component of the air-spinning device has a thread-forming element, e.g. a hollow spinning cone, which, in cooperation with the nozzle device, forms the thread which is drawn out of the spinning device through the hollow spinning cone. Opening the air-spinning device, in conjunction with the advantageously provided activation of the suction air flow generation device, e.g.It is particularly reliable that loose fiber material does not accumulate in the area of the spinneret and disrupt the spinning process, but is removed via the suction air flow generation device. This embodiment of the invention thus additionally ensures that the spinning process can be started and carried out smoothly after the drawn fiber sliver has been arranged.

[0022] According to a further embodiment of the invention, it is further provided that the drafting system is stopped after the fiber sliver has been transferred to the air-jet spinning device, the air-jet spinning device is closed, and the suction air flow generation device is deactivated. The interruption of the feeding process can be performed manually by the operating personnel or automatically. For this purpose, for example, a fiber sliver length or a time interval can be specified, after which the drafting system is automatically stopped.

[0023] This embodiment of the invention provides that after the fiber sliver has been positioned in the entry area of the air-jet spinning device, the insertion process via the drafting system is stopped. Following this, advantageously provided suction, possibly in conjunction with a similarly provided opening of the air-jet spinning device, contamination from loose fiber material can then be removed, and the air-jet spinning device can then be adjusted to the position required for the spinning process.

[0024] The spinning process can then be started, whereby disruptions are particularly effectively avoided.

[0025] An embodiment of the invention is explained below with reference to drawings.

[0026] The drawings show: Figure 1 shows a flow diagram of a method for arranging a fiber sliver on a spinning device of a spinning station; Figure 2 shows a schematic representation of an air-jet spinning device with upstream drafting system and Figure 3 shows a schematic representation of the air-jet spinning device of Figure 2 in the open state.

[0027] In Figure 1 is a process sequence for arranging a fiber sliver 3 via a drafting system 1 on an air spinning device 2 of a spinning station not shown here with reference to the Figure 2 and 3 in which the arrangement of drafting system 1 and air spinning device 2 of the spinning station is shown schematically in two positions.

[0028] To provide a drawn fiber sliver 3 at an inlet of the air-jet spinning device 2, the individually drivable roller pairs 5, 5a, 6, 6a, 7, 7a, 8, 8a of the drafting system 1 are operated in the closed state at an insertion speed which is significantly below the operating speed of the drafting system 1. At the same time, a compressed air source 13, which is connected via a line 12 to a spinneret unit 10, is activated to generate a suction flow in the area of the inlet of the air-jet spinning device 2, and the air-jet spinning device 2 is moved from its Figure 2 shown closed position into its Figure 3 shown open position, in which a spinning cone unit 15 is positioned opposite a nozzle device 4 opposite the position shown in Figure 2 shown operating position.

[0029] After activating the individually drivable roller pairs 5, 5a, 6, 6a, 7, 7a, 8, 8a of the drafting system 1 and providing compressed air via the compressed air source 13 while the air-jet spinning device 2 is open, the sliver 3 is manually inserted by the operating personnel into the clamping area of the input rollers 5, 5a. From there, after passing through the drafting system rollers 6, 6a, 7, 7a, the sliver 3 reaches the output rollers 8, 8a at a speed significantly reduced compared to regular operation of the spinning station, where the drawn sliver 3 exits the drafting system 1. The insertion speed of the drafting system rollers 5, 5a, 6, 6a, 7, 7a, 8, 8a is determined according to the drafting of the fiber sliver 3 to be achieved, so that the fiber sliver 3 exits the drafting system 1 according to the specified drafting ratio.By aligning the nozzles 10, 11 assigned to the spinneret unit 9 in a direction leading away from the inlet of the air-jet spinning device 2 or in a direction leading towards the spinning cone 16, the activated compressed air generates a suction air flow in the region of the inlet of the air-jet spinning device 2, via which suction air flow the fiber sliver 3 emerging from the drafting system 1 can be reliably fed to the air-jet spinning device 2. The suction air flow can preferably be supported by switching on the vacuum source 19 as needed. Switching on the vacuum source 19 also promotes the removal of fiber residues from the area of the air-jet spinning device 2, in particular the spinning cone 16. The drawn fiber sliver 3 is guided as needed via the output roller pair 8, 8a by means of the applied suction air flow to the inlet of the air-jet spinning device 2.After the free end 24 of the fiber sliver 3 has reached a defined position within the air-jet spinning device 2, the drafting system 1 is stopped and the compressed air source 13 and, if connected, the vacuum source 19 are deactivated. Following this, the air-jet spinning device 2 is moved from its . Figure 3 shown open position to the position shown in Figure 2 operating position shown.

[0030] The compressed air source 13, activated during the arrangement of the free end 24 of the fiber sliver 3 in the area of the air-jet spinning device 2, and optionally the connected vacuum source 19, ensures, among other things, that loose fiber materials are reliably removed from the area of the air-jet spinning device 2 and thus cannot lead to malfunctions in the operation of the air-jet spinning device 2. After the air-jet spinning device 2 is closed, the spinning process can be started by continuing the fiber sliver feed and applying a spinning pressure via the spinneret unit 9 and its associated nozzles 10, 11. List of reference symbols

[0031] 1Drafting system 2Air spinning device 3Sliver 4Nozzle device 5, 5aInput rollers 6, 6aDrafting system rollers 7, 7aDrafting system rollers 8, 8aOutput rollers 9Spinneret unit 10Nozzles 11Nozzles 12Line 13Compressed air source 15Spinning cone unit 16Spinning cone 17Swirl chamber 18Line 19Vacuum source 24Free end of the sliver

Claims

1. Method for arranging a fibre strand at a spinning device of a spinning station, wherein the fibre strand (3) is fed, by means of a drafting system (1) having several roller pairs (5, 5a, 6, 6a, 7, 7a, 8, 8a), to the spinning device (2) for the manufacture of a spun thread from the fibre strand (3), characterised in that - the roller pairs (5, 5a, 6, 6a, 7, 7a, 8, 8a) of the closed drafting system (1), which in particular are individually drivable, are each operated, in accordance with the predefined draft ratio of the fibre strand (3), at an insertion speed which is lower than the operating speed of the drafting system (1), - the fibre strand (3) is then inserted into the clamping area of an input roller pair (5, 5a) of the drafting system (1) and - the drafted fibre strand (3) is then fed to the spinning device (7) after passing through the closed drafting system (1) and exiting a clamping area of an output roller pair (8, 8a) of the drafting system (1).

2. Method according to claim 1, characterised in that the fibre strand (3), after passing through the drafting system (1), is fed to a spinning device designed as an air-jet spinning device (2).

3. Method according to claim 1 or 2, characterised in that a suction air flow generating device of the air-jet spinning device (2) is activated before or during the arrangement of the fibre strand (3) at the air-jet spinning device (2).

4. Method according to claim 3, characterised in that, after the fibre strand (3) has been transferred to the air-jet spinning device (2), the drafting system (1) is stopped, the air-jet spinning device (2) is closed and the suction air flow generating device is deactivated.

5. Method according to one or more of the preceding claims, characterised in that the air-jet spinning device (2) is opened before or during the arrangement of the fibre strand (3) at the air-jet spinning device (2).