SPINNING DEVICE, ROTOR SPINNING MACHINE AND METHOD FOR PREVENTING FIBER ACCUMULATION IN A SPINNING DEVICE

Description

[0001] The invention relates to a spinning device for producing yarn from a fiber material, a rotor spinning machine with at least one spinning device, and a method for preventing fiber accumulation within a rotor housing of a spinning device.

[0002] Various spinning devices are known from the prior art and are used to produce yarn from a fibrous material. In an open-end rotor spinning machine, individual textile fibers are typically fed in several spinning devices, formed as spinning boxes, to a spinning rotor rotating at high speed during spinning. There, they are spun into yarn, which is then drawn off the spinning rotor by means of a vacuum. The spinning device includes a rotor housing within which the spinning rotor is arranged. A rotor housing cover is typically provided for opening and closing the rotor housing.

[0003] During spinning, most of the supplied textile fibers are spun into yarn within the spinning rotor due to the high rotational speed, and the few released, unyielding individual fibers are removed from the spinning rotor area by means of the vacuum. However, when the spinning rotor is braked, for example, to open the rotor housing, the rotor speed eventually becomes insufficient to hold the textile fibers being spun in the rotor groove. Furthermore, the vacuum must also be deactivated to open the rotor housing. Both of these factors can lead to fiber material becoming distributed inside the spinning device. In particular, a fiber ring, known as a "donut," located within the spinning rotor can also break free during braking.Fiber material or the fiber ring can enter an area behind the spinning rotor and contaminate or entangle the rotor bearings, typically leading to a failure of the rotor spinning machine after a short time. This problem occurs in all spinning devices of a rotor spinning machine. However, it is particularly problematic in spinning devices with a single drive for the spinning rotor and / or with contactless magnetic bearings, as the ingress of fiber material or even a fiber ring into the bearing gap or entanglement with the spinning rotor shaft immediately leads to failure of the spinning device when the spinning rotor is accelerated again.

[0004] The prior art document DE 10 2015 016 594 A1 proposes that, when braking the spinning rotor, the vacuum should first be deactivated at a rotational speed where a fiber ring is still held within the rotor. The rotor should then be pivoted by at least partially opening the rotor housing so that, upon further braking, the fiber ring can fall out of the rotor groove. The vacuum is then reactivated to extract the fallen fiber ring and the fiber material. However, this prior art solution has the disadvantage that, for a period of time, the rotational speed of the spinning rotor is insufficient to hold the fiber ring within the rotor, while the vacuum has not yet been reactivated. Therefore, it is not entirely certain that the fiber ring cannot still enter the area behind the spinning rotor.Furthermore, the weight of the fiber ring fluctuates, and its position after falling from the spinning rotor also varies. Therefore, a sufficient volume flow cannot always be generated by the vacuum to reliably remove the fiber ring and fiber material from the spinning device. Consequently, even with this state-of-the-art solution, operational interruptions due to winding or bearing contamination can still occur.

[0005] JP S54 150522 U discloses a device for preventing the accumulation of fiber waste around a spinning rotor in an open-end spinning machine. The device comprises an annular air inlet groove arranged in an outer wall surface of a housing that surrounds the spinning rotor, its drive shaft, and the bearing. The device also includes a suitable number of ventilation holes in an inner wall surface of the housing between the bearing and an outlet hole in the spinning rotor, arranged to communicate with the air inlet groove. An annular filter element is arranged to cover the open surface of the air inlet groove opposite the ventilation holes.

[0006] The invention is based on the objective of providing a spinning device, a rotor spinning machine and a method that enable particularly reliable and trouble-free operation regardless of the number of interruptions to the spinning operation.

[0007] The object of the invention is achieved by a spinning device according to claim 1, a rotor spinning machine according to claim 7, and a method for preventing fiber accumulation within a rotor housing of a spinning device according to claim 9. Advantageous embodiments of the invention are specified in the dependent claims.

[0008] The spinning device according to the invention for producing yarn from a fiber material comprises a rotor housing, a spinning rotor arranged within the rotor housing and rotating at high speed during spinning operation, and a rotor housing cover arranged on the rotor housing for opening and closing the rotor housing, wherein a device for generating at least one barrier gas flow designed as a compressed air flow is also arranged at least sectionally within the rotor housing in a region of the rotor housing behind the spinning rotor or in the region of a spinning rotor rear side, in order to prevent fiber material and / or a fiber ring from getting behind the spinning rotor when the spinning rotor is braked and / or when the rotor housing cover is opened.

[0009] The invention further relates to a rotor spinning machine with at least one spinning device according to the invention and preferably several, in particular preferably identical, spinning devices according to the invention.

[0010] The inventive method for preventing fiber accumulation within a rotor housing of a spinning device, comprising a spinning rotor arranged within the rotor housing and rotating at high speed during spinning operation, and a rotor housing cover arranged on the rotor housing for opening and closing the rotor housing, comprises a process step in which, before opening the rotor housing and / or when braking the rotating spinning rotor, in particular for the subsequent opening of the rotor housing, a barrier gas stream designed as a compressed air stream is directed onto an area of ​​the rotor housing behind the spinning rotor or onto the area of ​​a spinning rotor rear side or spinning rotor rear wall, in order to prevent fiber material and / or a fiber ring from entering behind the spinning rotor. The direction of the barrier gas stream is particularly preferably carried out by means of a device according to the invention for generating at least one barrier gas stream.

[0011] The spinning device can initially be any device or assembly for producing threads, yarns, or twines. Preferably, the spinning device is a spinning box, in particular a rotor spinning machine, and most preferably an open-end rotor spinning machine. The spinning machine can have one or more spinning stations, each designed for producing a thread, wherein each spinning station is most preferably designed as a spinning device or spinning box and most preferably comprises exactly one spinning rotor.

[0012] A yarn or thread produced according to the invention is a fiber composite, preferably formed from individual fibers twisted around one another. These fibers can be made of a natural material, such as wool or cotton, and / or a synthetic material, such as polyester or polyethersulfone. The fiber material is preferably fed to the spinning apparatus in the form of a fiber spool, also called a spool, and the individual fibers are preferably separated before spinning.

[0013] The rotor housing essentially surrounds the spinning rotor, which rotates at high speed during spinning operations, and is preferably subjected to a vacuum during spinning. To allow access to the spinning rotor, the rotor housing, according to the invention, has a rotor housing cover, which is preferably pivotably mounted on the rotor housing. For opening and closing the rotor housing, the rotor housing cover is preferably movable between an open and a closed position and, more preferably, pivotable. Furthermore, it is more preferably the case that the spinning rotor is accessible in the open position of the rotor housing cover and / or substantially completely covered or inaccessible to a user in the closed position.

[0014] According to the invention, a device for generating at least one blocking gas stream is provided, which is generally designed to release at least one gas stream in a defined direction. Preferably, the device for generating at least one blocking gas stream has at least one gas outlet opening and, in particular, a gas outlet nozzle, which may, in particular, be part of a blowing channel. Each blowing channel generally has at least one such gas outlet opening or gas outlet nozzle. The device for generating at least one blocking gas stream is preferably intended to prevent winding and / or a crash due to winding or bearing contamination, especially during the restart of the spinning rotor. Alternatively or additionally, the device for generating at least one blocking gas stream is intended to prevent clogging of the spinning rotor bearing in the long term.

[0015] The device is particularly preferably designed to simultaneously release several barrier gas streams and / or to block off or protect an area from fiber material and / or a fiber ring by means of directed gas streams. This is particularly preferably achieved by one or more barrier gas streams flowing away from the area to be protected. According to the invention, the barrier gas stream is a compressed air stream.

[0016] The area to be protected by the barrier gas stream(s), or the area toward which the barrier gas stream(s) are directed, is preferably an area on and / or behind the spinner rotor's rear face or rear wall. Particularly preferably, the area to be protected extends between the spinner rotor's rear wall and the opposite wall of the rotor housing. Particularly preferably, the area to be protected also includes a bearing of the spinner rotor. Most preferably, the barrier gas stream flows around the spinner rotor from the rear, encompassing its entire circumference.

[0017] According to the invention, the device for generating at least one barrier gas flow is arranged at least section by section within the rotor housing in a region of the rotor housing behind the spinning rotor or in the region of a spinning rotor back face, in order to protect this region. It is also possible for only gas outlet openings or gas outlet nozzles to be directed into the interior of the rotor housing, while the remaining components of the device for generating at least one barrier gas flow are arranged in the rotor housing wall and / or outside the rotor housing. It is further preferred that the device is located inside the rotor housing only on the side of the rotor housing facing a spinning rotor back face and optionally also in the material of the rotor housing and / or outside the rotor housing. Furthermore, the device for generating at least one barrier gas flow can be formed section by section or completely integrally with the rotor housing.

[0018] Fiber clumps, and especially fiber rings, form particularly when fiber material not drawn off during spinning remains in the spinning rotor. These clumps, and especially fiber rings, can then be drawn behind the spinning rotor when the rotor housing is opened and / or when the vacuum is deactivated. Fiber clumps are particularly characteristic of so-called "donuts," i.e., ring-shaped fiber aggregates or fiber rings that form during operation of the spinning rotor and can be drawn out of the spinning rotor and into the rotor housing, especially when the spinning rotor stops or when a minimum rotational speed is reached. In principle, however, fiber clumps can have any shape and size and can be composed of any number of individual fibers.

[0019] A preferred embodiment of the spinning device according to the invention for producing yarn has at least one rotor housing arranged on the rotor housing and / or on the

[0020] The device features a blow channel directed towards the rear of the spinning rotor, enabling the channeling of a barrier gas stream onto a protected area. The term "blow channel" is initially understood to refer only to the portion of the device for generating at least one barrier gas stream that directs the stream directly onto the rear of the spinning rotor. The blow channel can extend in any way within and / or behind the rotor housing and / or be connected to another device, additional compressed air lines or channels, or be connected to other blow channels of the same spinning device or to another spinning device. Preferably, the blow channel(s) are arranged in an area behind the spinning rotor or opposite the rear of the spinning rotor, particularly on the rotor housing. Furthermore, it is more preferably the device for generating at least one barrier gas stream is formed integrally with the rotor housing.Alternatively or additionally, the blow channel preferably runs within the wall of the rotor housing.

[0021] Although a protective function can in principle be achieved by means of a single blow channel, a device for generating at least one barrier gas stream is preferred, which has at least two, preferably between 3 and 12, particularly preferably between 4 and 10, and most preferably between 6 and 8 blow channels. Preferably, each blow channel has exactly one opening directed towards the spinning rotor and, in particular, towards the rear of the spinning rotor, which is formed to direct the barrier gas stream to the rear of the spinning rotor.

[0022] An advantageous embodiment of the spinning device for producing yarn further provides that the blow channels are arranged circularly and / or uniformly around a rotational axis of the spinning rotor on the rotor housing. A uniform arrangement refers in particular to an equal distance from the spinning rotor axis and / or an equal distance from adjacent blow channels and / or an equally spaced arrangement on a circle, especially around the spinning rotor axis. The blow channels are preferably arranged on an inner wall of the rotor housing and / or in an area of ​​the rotor housing covered by the spinning rotor with respect to the opening of the rotor housing or the rotor housing cover. Furthermore, the blow channels are preferably arranged behind the spinning rotor with respect to the opening of the rotor housing or the rotor housing cover.

[0023] The distance of the blowing channel(s) from the axis of rotation of the [unclear text] is also preferred.

[0024] The radius of the spinner rotor is smaller than the radius of the spinner rotor, particularly preferably less than 90%, very preferably less than 80%, and particularly preferably less than 75% of the radius of the spinner rotor. Alternatively or additionally, the distance of the blowing channel(s) from the axis of rotation of the spinner rotor is greater than 10%, particularly preferably greater than 25%, very preferably greater than 50%, and particularly preferably greater than 75% of the radius of the spinner rotor.

[0025] In a preferred embodiment of the spinning device according to the invention for producing yarn, the angle of the blow channel(s) in relation to the rotational axis of the spinning rotor is between 0° and 45°, preferably between 0° and 30°, and particularly preferably between 5° and 20°, at least in the area provided for the exit of the barrier gas flow, such that the barrier gas flow is directed towards the outer edge of the spinning rotor and / or the barrier gas flows along the rear side of the spinning rotor in the direction of the outer edge of the spinning rotor. Furthermore, the blow channel can also be aligned parallel to the spinning rotor axis. The angle of the blow channel is the angle between the central longitudinal axis of the spinning rotor axis and the central longitudinal axis of the opening or end region of the blow channel for the exit of the barrier gas flow.

[0026] A further preferred embodiment of the spinning device for producing yarn provides that the blow channels are connected to an annular air distributor, which is preferably formed as a single unit or integrally with the rotor housing and / or connected to a compressed air connection on the outside of the rotor housing. Particularly preferably, the air distributor is formed entirely integrally with the rotor housing. Alternatively, however, the air distributor can also be formed as a component arranged on the rotor housing and / or form part of the rotor housing. Furthermore, the air distributor can be arranged partially or completely inside and / or outside the rotor housing.

[0027] Although a rotor spinning machine with a central drive for several spinning units and, in particular, several spinning rotors is also conceivable, the device according to the invention for generating at least one blocking gas flow is preferably used with one or more spinning units of a rotor spinning machine in which each spinning rotor is individually driven and / or preferably mounted without contact, in particular magnetically. With a non-contact mounting of the spinning rotor, it is particularly important to avoid contamination with fiber material in the area of ​​the mounting, as otherwise the operation will be disrupted when the spinning rotor restarts. The drive of the spinning rotor is, in particular, preferably an individual electric motor drive.

[0028] An advantageous embodiment of the method for preventing fiber accumulation within the rotor housing of a spinning device provides that the barrier gas flow is deactivated during the spinning process for producing yarn from a fiber material using the spinning rotor and / or that the barrier gas flow is activated at a predetermined time, preferably between 0.5 s and 10 s, particularly preferably between 1 s and 5 s, and most preferably between 1 s and 2 s, before the rotor housing is opened. The opening of the rotor housing preferably occurs automatically. Alternatively or additionally, manual opening after automatic unlocking of an openable rotor housing cover is also possible, wherein the activation of the barrier gas flow by a predetermined time interval before unlocking or automatic opening is particularly preferred.

[0029] Alternatively or additionally, a preferred embodiment of the method for preventing fiber accumulation within a rotor housing of a spinning device is also preferred, in which the barrier gas flow is deactivated during the spinning process for producing yarn from a fiber material using the spinning rotor and / or the barrier gas flow is activated when the spinning rotor is braked, depending on the rotor speed, preferably when the rotor speed falls below 50,000 rpm, particularly preferably 30,000 rpm and most preferably 20,000 rpm, since from a corresponding rotational speed the fiber material is no longer sufficiently held in a fiber ring of the spinning rotor and can thus get behind the spinning rotor or towards the back of the spinning rotor.

[0030] Furthermore, it is preferred that the barrier gas flow is deactivated at a predetermined time after the rotor housing is opened, preferably between 0.5 s and 10 s, particularly preferably between 1 s and 5 s, and most preferably between 1 s and 2 s. Alternatively, the barrier gas flow can remain activated as long as the rotor housing cover is open and only be deactivated when the rotor housing is completely closed and / or when the spinning rotor starts up, in particular when a minimum rotor speed is reached, preferably 50,000 rpm, particularly preferably 30,000 rpm, and most preferably 20,000 rpm.

[0031] The spinning process generally takes place within a closed rotor housing and under a vacuum applied to the rotor housing. There is also a correlation between the presence of this vacuum and the risk of fiber material, and in particular a fiber ring, being drawn into an area behind the spinning rotor. Accordingly, a further development of the method for preventing fiber accumulation within the rotor housing of a spinning device is preferred in which the barrier gas flow is activated before the vacuum required for spinning is released within the rotor housing. Alternatively, the activation of the barrier gas flow can also occur simultaneously with the deactivation of the vacuum.

[0032] An embodiment of the device according to the invention for generating at least one barring gas flow in a spinning junction is explained in more detail below with reference to the drawings. The figures show: Fig. 1 is a perspective view of a rotor housing with a spinning rotor and a device for generating at least one blocking gas flow for a spinning device, and Fig. 2 is a perspective sectional view of the in Fig. 1 The depicted rotor housing includes a device for generating at least one blocking gas flow.

[0033] A section-by-section in the Figure 1 The illustrated spinning device of a rotor spinning machine has at least one spinning rotor 2 that rotates at high speed during spinning operation and is arranged within a rotor housing 1. For spinning operation, the rotor housing 1 is closed and a vacuum is applied. To allow the rotor housing 1 to be opened, a rotor housing cover is provided, which is pivotably mounted on the rotor housing 1.

[0034] To spin yarn from a fibrous material, individual fibers are fed to the spinning rotor 2. If the spinning process needs to be interrupted, the spinning rotor 2 is braked so that the rotor housing 1 can be opened. However, if the spinning rotor 2 falls below a speed typically between 50,000 and 20,000 rpm, the centrifugal forces are no longer sufficient to hold the fibers inside the spinning rotor 2, allowing a clump of fibers, particularly a fiber ring, to escape from the spinning rotor 2 into the interior of the rotor housing 1. If the fiber ring reaches an area in front of the spinning rotor 2 or between the spinning rotor and an openable rotor housing cover, this is not a problem, as the fiber ring is removed when the rotor housing 1 is opened. If the fiber ring reaches a point where it is trapped, the spinning rotor 2 becomes trapped, and the fiber ring is removed.If, on the other hand, fiber accumulations occur in an area behind the spinning rotor 2 and especially in the area of ​​the spinning rotor axis, an electromechanical spinning rotor drive and / or a magnetic spinning rotor bearing, this can lead to a malfunction, especially when restarting the spinning rotor 2.

[0035] To prevent this, a device 3 for generating a barrier gas flow is arranged in the area of ​​the rotor housing 1 behind the spinning rotor 2 (see Fig. 1 ), by means of which several purge gas streams can be directed onto an area behind the spinning rotor when the spinning rotor 2 is braked, so that no fiber ring or fiber accumulations can enter this protected area. For this purpose, eight blow channels 5 of the device 3 for generating a purge gas stream are arranged uniformly along a circle around the spinning rotor axis on the rotor housing 1 behind the spinning rotor 2 (see Fig. 2) that a barrier gas flow can be directed towards the rear of the spinning rotor 4 by means of each of the blow channels 5, so that the barrier gas flows in an area between the rear wall of the rotor housing 1 and the rear of the spinning rotor 4 and then continues radially along the rear of the spinning rotor 4 towards the front of the spinning rotor 2, so that no fiber rings can enter this area. An outlet opening of each blow channel 5 is arranged at an angle of approximately 30° with respect to the axis of rotation of the spinning rotor 2 and radially away from the center of the spinning rotor.

[0036] To supply the individual blow channels 5 with compressed air, these are connected inside the wall of the rotor housing 1 to an annular air distributor 6, which is supplied via a compressed air connection 7 located on the outside of the rotor housing 1. All blow channels 5, and in particular all openings of the blow channels 5 for the exit of sealing gas, are identical to each other and / or have a round cross-section. Reference symbol list

[0037] 1 Rotor housing 2 Spin rotor 3 Device for generating a barrier gas flow 4 Spin rotor back 5 Blow duct 6 Air distributor 7 Compressed air connection

Claims

1. Spinning device for producing a yarn from a fiber material, comprising - a rotor housing (1), - a spinning rotor (2) arranged within the rotor housing (1) and revolving at high speed during spinning operation, and - a rotor housing lid arranged on the rotor housing (1) for opening and closing the rotor housing (1), - a device (3) arranged at least in portions within the rotor housing (1) for generating at least one flow of sealing gas in the form of a compressed air flow in a region at the rear of the spinning rotor (4), in order to prevent fiber material and / or a loop of fibers from entering the spinning rotor (2) when the spinning rotor is braked (2) and / or when the rotor housing lid is opened.

2. Spinning device for producing a yarn according to claim 1, characterized in that the device (3) for generating at least one flow of sealing gas has at least one blowing channel (5) arranged on the rotor housing (1) and directed toward the rear of the spinning rotor (4).

3. Spinning device for producing a yarn according to claim 2, characterized in that the device (3) has at least two blowing channels (5) for generating at least one flow of sealing gas.

4. Spinning device for producing a yarn according to claim 3, characterized in that the blowing channels (5) are arranged on the rotor housing (1) in a circular and / or uniform manner about an axis of rotation of the spinning rotor (2).

5. Spinning device for producing a yarn according to claim 3 or 4, characterized in that the angle of the blowing channels (5) in each case in relation to the axis of rotation of the spinning rotor (2) is between 0° and 45°, preferably between 0° and 30°, and particularly preferably between 5° and 20°.

6. Spinning device for producing a yarn according to one of the claims 3 to 5, characterized in that the blowing channels (5) are connected to a ring-shaped air distributor (6) which is connected to a compressed air connection (7) on the outside of the rotor housing (1).

7. Rotor spinning machine having at least one spinning device according to at least one of claims 1 to 6.

8. Rotor spinning machine according to claim 7, characterized in that each spinning rotor (2) is individually driven and / or mounted contactlessly.

9. Method for preventing the accumulation of fibers within a rotor housing (1) of a spinning device comprising - a spinning rotor (2) arranged within the rotor housing (1) and revolving at high speed during spinning operation, and - a rotor housing lid arranged on the rotor housing (1) for opening and closing the rotor housing (1), wherein - before the rotor housing (1) is opened and / or when the running spinning rotor (2) is braked, a flow of sealing gas in the form of a compressed air flow is directed to a region of the rotor housing (1) at the rear of the spinning rotor (4) in order to prevent fiber material and / or a loop of fibers from getting behind the spinning rotor (2).

10. Method for preventing the accumulation of fibers within a rotor housing (1) of a spinning device according to claim 9, characterized in that the flow of sealing gas is deactivated during the spinning process for producing a yarn from a fiber material by means of the spinning rotor (2), and the flow of sealing gas is activated at a predetermined time between 1s and 5s before the rotor housing (1) is opened.

11. Method for preventing the accumulation of fibers within a rotor housing (1) of a spinning device according to either claim 9 or claim 10, characterized in that the flow of sealing gas is deactivated during the spinning process for producing a yarn from a fiber material by means of the spinning rotor (2), and the flow of sealing gas is activated when the spinning rotor is braked (2), as a function of the rotor speed, when a rotor speed drops below 20,000 1 / min.

12. Method for preventing the accumulation of fibers within a rotor housing (1) of a spinning device according to at least one of the preceding claims 9-11, characterized in that the flow of sealing gas is deactivated at a predetermined time between 1s and 5s after the rotor housing (1) has been opened.

13. Method for preventing the accumulation of fibers within a rotor housing (1) of a spinning device according to at least one of the preceding claims 9-12, characterized in that the flow of sealing gas is activated before a vacuum applied to the spinning operation within the rotor housing (1) is shut off.